Filed pursuant to Rule 424(b)(5)
Registration No. 333-216737

The information in this preliminary prospectus supplement and the accompanying prospectus is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell the securities nor do they seek an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

Subject to completion, dated September 10, 2018

Preliminary prospectus supplement

(To Prospectus dated April 19, 2017)

12,500,000 shares

NN, Inc.

Common stock

We are offering 12,500,000 shares of our common stock, par value $0.01 per share, which we refer to as our “common stock,” pursuant to this prospectus supplement and the accompanying prospectus.

Our common stock is listed on The Nasdaq Global Select Market, which we refer to as “Nasdaq,” under the trading symbol “NNBR.” On September 7, 2018, the last sale price of our common stock as reported on Nasdaq was $19.95 per share.

This investment involves risks. See “Risk factors” beginning on page S-12 of this prospectus supplement and in the documents we incorporate by reference into this prospectus supplement and the accompanying prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved of anyone’s investment in these securities or determined if this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The underwriters may also purchase up to an additional 1,875,000 shares of our common stock from us, at the public offering price less the underwriting discount, within 30 days from the date of this prospectus supplement.

We expect the shares to be delivered against payment in New York, New York on                     , 2018.

Prospectus supplement dated                     , 2018.

Table of contents

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We have not, and the underwriters have not, authorized anyone to provide any information or to make any representations other than those contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectuses we have prepared and take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus supplement and the accompanying prospectus are an offer to sell only the shares offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. The information contained in this prospectus supplement and the accompanying prospectus is current only as of its date. Our business, financial condition, results of operation and prospects may have changed since that date.

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About this prospectus supplement

This document has two parts, a prospectus supplement and an accompanying prospectus dated April 19, 2017. This prospectus supplement and the accompanying prospectus are part of a registration statement that we filed with the Securities and Exchange Commission, which we refer to as the SEC, utilizing the SEC’s “shelf” registration process. This prospectus supplement, which describes certain matters relating to us and the specific terms of this offering of shares of common stock, adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference herein and in the accompanying prospectus. Generally, when we refer to this document, we are referring to both parts of this document combined. Both this prospectus supplement and the accompanying prospectus include important information about us, our common stock and other information you should know before investing in our common stock. The accompanying prospectus gives more general information, some of which may not apply to the shares of common stock offered by this prospectus supplement. To the extent the information contained in this prospectus supplement differs or varies from the information contained in the accompanying prospectus, you should rely on the information contained in this prospectus supplement. If the information contained in this prospectus supplement differs or varies from the information contained in a document we have incorporated by reference, you should rely on the information in the more recent document.

Before you invest in our common stock, you should read the registration statement of which this document forms a part and this document, including the documents incorporated by reference herein that are described under the heading “Incorporation by reference.”

The distribution of this prospectus supplement and the accompanying prospectus and the offering of the common stock in certain jurisdictions may be restricted by law. Neither we nor the underwriters are making an offer of the common stock in any jurisdiction where the offer is not permitted. Persons who come into possession of this prospectus supplement and the accompanying prospectus should inform themselves about and observe any such restrictions. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer or solicitation by anyone in any jurisdiction in which such offer or solicitation is not authorized or in which the person making such offer or solicitation is not qualified to do so or to any person to whom it is unlawful to make such offer or solicitation.

You should not consider any information in this prospectus supplement or the accompanying prospectus to be investment, legal or tax advice. You should consult your own counsel, accountant and other advisors for legal, tax, business, financial and related advice regarding the purchase of the common stock. Neither we nor the underwriters are making any representation to you regarding the legality of an investment in the common stock by you under applicable investment or similar laws.

Industry and market data

Some market data and other statistical information presented or incorporated by reference in this prospectus supplement are based on data from various independent third-party sources, including independent industry publications, reports by market research firms and other independent sources. Other data is based on management’s estimates and calculations, which are derived from our review and interpretation of internal analyses, as well as third party sources. Although we believe these third party sources are reliable, we have not independently verified any information and cannot guarantee its accuracy and completeness. To the extent that we have been unable to obtain information from third party sources, we have expressed our belief on the basis of our own internal analyses of our products and capabilities in comparison to our competitors.

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Trademarks and trade names

This prospectus supplement contains references to our trademarks and service marks and to those belonging to other entities. Solely for convenience, trademarks and trade names referred to in this prospectus may appear without the ^® or ™ symbols, but such references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or the rights of the applicable licensor to these trademarks and trade names. We do not intend our use or display of other companies’ trade names, trademarks or service marks to imply a relationship with, or endorsement or sponsorship of us by, any other companies.

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Risk factors

Investing in our common stock involves risks. You should carefully consider the risks and uncertainties described below as well as those contained in our Annual Report on Form 10-K for the fiscal year ended December 31, 2017, including our consolidated financial statements and the related notes, which are incorporated by reference into this prospectus supplement and the accompanying prospectus. These risks could materially affect our business, results of operations or financial condition and cause the value of our common stock to decline. You could lose all or part of your investment.

Risks related to the acquisition

We may not realize the growth opportunities, operational synergies and other benefits that are anticipated from the Acquisition.

The benefits that are expected to result from the Acquisition will depend, in part, on our ability to realize the growth opportunities and operational synergies we anticipate from the Acquisition. Our success in realizing these growth opportunities and operational synergies, and the timing of this realization, depends, in part, on the successful integration of Paragon. Even if we are able to integrate Paragon successfully, this integration may not result in the realization of the full benefits of the growth opportunities and operational synergies that we currently expect, nor can we give assurances that these benefits will be achieved when expected or at all. For example, we may not be able to eliminate duplicative costs. Moreover, we also expect to incur expenses in connection with the integration of Paragon. While it is anticipated that certain expenses will be incurred to achieve operational synergies, such expenses are difficult to estimate accurately, and may exceed current estimates. Accordingly, the benefits from the Acquisition may be offset by costs incurred or delays in integrating the businesses. In addition, the integration of Paragon may result in material unanticipated problems, expenses, liabilities, regulatory risks, competitive responses, and diversion of management’s attention.

The following factors, among others, may negatively affect the anticipated benefits of the Acquisition and our ability to integrate Paragon into our operations:

The integration of Paragon could adversely affect our business, financial results, and operations and the market price of shares of our common stock.

The integration of Paragon could cause disruptions and create uncertainty surrounding our business and affect our relationships with our customers and employees. In addition, we have diverted, and will continue to divert, significant management resources to complete the work associated with the Acquisition, which could have a negative impact on our ability to manage existing operations or pursue alternative strategic transactions, which could adversely affect our business, financial condition and results of operations. As a result of investor perceptions about the terms or benefits of the Acquisition, the market price of shares of our common stock may decline.

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Risks related to this offering and ownership of our common stock

Management will have broad discretion over the use of the remaining net proceeds from this offering and may apply the net proceeds in ways that do not improve our operating results or increase the value of your investment.

We intend to use the net proceeds from this offering to repay a portion of the debt financing that was provided in connection with the Acquisition. Our management will have broad discretion in the application of any remaining net proceeds from this offering and could spend such net proceeds in ways that do not improve our results of operations or enhance the value of our common stock. Our failure to apply these funds effectively could have a material adverse effect on our business and cause the price of our common stock to decline.

The price of our common stock may be volatile.

The market price of our common stock could be subject to significant fluctuations and may decline. Among the factors that could affect our stock price are:

The stock markets in general have experienced extreme volatility that has often been unrelated to the operating performance of particular companies. These broad market fluctuations may adversely affect the trading price of our common stock. You may not be able to sell your shares of our common stock at or above the public offering price, or at all. In addition, due to the market capitalization of our stock, our stock tends to be more volatile than large capitalization stocks that comprise the Dow Jones Industrial Average or Standard and Poor’s 500 Index. Any volatility of or a significant decrease in the market price of our common stock could also negatively affect our ability to make acquisitions using our common stock.

We are able to issue shares of preferred stock with greater rights than our common stock.

Our Board of Directors is authorized to issue one or more series of preferred stock from time to time without any action on the part of our stockholders. Our Board of Directors also has the power, without stockholder approval, to set the terms of any such series of preferred stock that may be issued, including voting rights, dividend rights and preferences over our common stock with respect to dividends and other terms. If we issue preferred stock in the future that has a preference over our common stock with respect to the payment of dividends or other terms, or if we issue preferred stock with voting rights that dilute the voting power of our common stock, the rights of holders of our common stock or the market price of our common stock could be adversely affected.

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Future sales of our common and preferred stock may depress the price of our common stock.

As of August 31, 2018, there were 27,729,375 shares of our common stock outstanding, 778,048 shares of common stock issuable upon the exercise of outstanding stock options, and an additional 352,121 shares of our common stock that may be issued in connection with outstanding equity awards held by management, other employees and directors. As of August 31, 2018, 1,550,170 shares of our common stock were available for future awards pursuant to our equity compensation plans without stockholder approval. We also have the authority to issue up to 5,000,000 shares of preferred stock upon terms that are determined by our Board of Directors. In addition, in 2017, we registered with the SEC the potential issuance of debt securities, shares of preferred stock, shares of common stock, warrants and units of the Company in an amount up to $400,000,000 on a registration statement on Form S-3 (which amount includes the shares of common stock that may be issued and sold pursuant to this offering). These securities, if issued, may be used for working capital and general corporate purposes, or used in future acquisitions, subject to the covenants of any existing and future outstanding indebtedness. Sales of a substantial number of these securities in the public market, or factors relating to the terms we may determine for our common stock, preferred stock, debt securities, warrants, units and options, could decrease the market price of our common stock. In addition, the perception that such sales might occur may cause the market price of our common stock to decline. Future issuances or sales of our common stock could have an adverse effect on the market price of our common stock or make it more difficult for you to sell your shares of our common stock at a time and price that you deem appropriate.

In addition, as described under the caption “Underwriting (conflicts of interest),” our directors and executive officers have agreed, subject to certain exceptions, not to offer, sell or contract to sell, directly or indirectly, any shares of our common stock for a period of 90 days from the date of this prospectus supplement. Sales of a substantial number of such shares upon expiration of such period, or the perception that such sales might occur, could have an adverse effect on the market price of our common stock or make it more difficult for you to sell your shares of our common stock at a time and price that you deem appropriate.

Your percentage of ownership in us may be diluted in the future.

As with any publicly traded company, your percentage ownership in us may be diluted in the future because of equity issuances for acquisitions, capital market transactions or otherwise, including equity awards that we expect will be granted to our directors, officers and employees.

Provisions in our charter documents and Delaware law may inhibit a takeover, which could adversely affect the value of our common stock.

Our certificate of incorporation and bylaws, as well as Delaware corporate law, contain provisions that could delay or prevent a change of control or changes in our management that a stockholder might consider favorable and may prevent shareholders from receiving a takeover premium for their shares. These provisions include, for example, a classified board of directors and the authorization of our board of directors to issue up to five million preferred shares without a stockholder vote. In addition, our certificate of incorporation provides that stockholders may not call a special meeting.

We are a Delaware corporation subject to the provisions of Section 203 of the Delaware General Corporation Law, an anti-takeover law. Generally, this statute prohibits a publicly-held Delaware corporation from engaging in a business combination with an interested stockholder for a period of three years after the date of the transaction in which such person became an interested stockholder, unless the business combination is approved in a prescribed manner. A business combination includes a merger, asset sale or other transaction resulting in a financial benefit to the stockholder. We anticipate that the provisions of Section 203 may

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encourage parties interested in acquiring us to negotiate in advance with our board of directors, because the stockholder approval requirement would be avoided if a majority of the directors then in office approve either the business combination or the transaction that results in the stockholder becoming an interested stockholder. These provisions apply even if the offer may be considered beneficial by some of our stockholders. If a change of control or change in management is delayed or prevented, the market price of our common stock could decline.

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Cautionary statement regarding forward-looking statements

This prospectus supplement and the accompanying prospectus contain or incorporate by reference “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and the Private Securities Litigation Reform Act of 1995, that reflect our current views with respect to, among other things, our operations and financial performance. These forward-looking statements include statements concerning our plans, objectives, goals, strategies, future events, future revenue or performance, capital expenditures, financing needs, plans or intentions relating to acquisitions, business trends, and other information that is not historical information and, in particular, appear under “Business,” “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations.” Forward-looking statements include all statements that are not historical facts. In some cases, you can identify these forward-looking statements by the use of words such as “outlook,” “believes,” “expects,” “potential,” “continues,” “may,” “will,” “should,” “could,” “seeks,” “predicts,” “intends,” “plans,” “estimates,” “anticipates,” “projects,” “forecasts” or the negative version of these words or other comparable words. All forward-looking statements, including, without limitation, management’s examination of historical operating trends and data are based upon our current expectations and various assumptions. Our expectations, beliefs, and projections are expressed in good faith and we believe there is a reasonable basis for them. However, we cannot assure you that these expectations, beliefs and projections will be achieved. Forward-looking statements are not guarantees of future performance and are subject to significant risks and uncertainties that may cause actual outcomes, results or achievements to be materially different from the future results or achievements expressed or implied by the forward-looking statements. Factors that could materially affect actual results include, but are not limited to: general economic conditions and economic conditions in the industrial sector, inventory levels, regulatory compliance costs and our ability to manage these costs, start-up costs for new operations, debt reduction, competitive influences, risks that current customers will commence or increase captive production, risks of capacity underutilization, quality issues, availability and price of raw materials, currency and other risks associated with international trade, our dependence on certain major customers, and the successful implementation of the global growth plan, including development of new products. Similarly, statements made herein and elsewhere regarding pending or completed acquisitions are also forward-looking statements, including statements relating to the anticipated closing date of an acquisition, our ability to obtain required regulatory approvals or satisfy closing conditions, the costs of an acquisition and our source(s) of financing, the future performance and prospects of an acquired business, the expected benefits of an acquisition on our future business and operations and our ability to successfully integrate recently acquired businesses.

These factors should not be construed as exhaustive and should be read in conjunction with the other cautionary statements that are included or incorporated by reference in this prospectus supplement and the accompanying prospectus. We operate in a very competitive and challenging environment. New risks and uncertainties emerge from time to time, and it is not possible for us to predict all risks and uncertainties that could have an impact on the forward-looking statements contained or incorporated by reference in this prospectus supplement and the accompanying prospectus. We cannot assure you that the results, events and circumstances reflected in the forward-looking statements will be achieved or occur, and actual results, events, or circumstances could differ materially from those described in the forward-looking statements.

The forward-looking statements made or incorporated by reference in this prospectus supplement and the accompanying prospectus relate only to events as of the date on which the statements are made. We undertake no obligation to publicly update or review any forward-looking statement, whether as a result of new information, future developments or otherwise, except as required by law. We may not actually achieve the

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plans, intentions or expectations disclosed in our forward-looking statements and you should not place undue reliance on our forward-looking statements. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, joint ventures, investments or other strategic transactions we may make.

For additional information concerning such risk factors and cautionary statements, please see the section titled “Risk Factors” in this prospectus supplement as well as in our Annual Report on Form 10-K for the fiscal year ended December 31, 2017 and our other reports on file with the SEC.

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Use of proceeds

We estimate the net proceeds to us from the offering to be approximately $                 million (approximately $                 million if the underwriters exercise their option to purchase additional shares of common stock), after deducting the underwriting discount and our estimated offering expenses.

We intend to use the net proceeds from this offering to repay the Second Lien Facility and the remaining net proceeds, if any, for general corporate purposes.

As of August 31, 2018, approximately $200 million of borrowings were outstanding under the Second Lien Facility, which bears interest at a variable interest rate, which as of August 31, 2018, was 10.1% per annum, and matures on April 19, 2023. Borrowings under the Second Lien Facility were used to pay a portion of the purchase price of the Acquisition. Pending application of the net proceeds for the purposes described above, we may temporarily invest the net proceeds in short term securities.

Affiliates of some or all of the underwriters participating in this offering are lenders under the Second Lien Facility and, accordingly, such affiliates will receive a portion of the net proceeds of this offering through the repayment of borrowings under the Second Lien Facility. See “Underwriting (conflicts of interest).”

Market price of common stock

Our common stock is traded on The Nasdaq Global Select Market under the symbol “NNBR.” The following table sets forth for the periods indicated the high and low intra-day sale prices per share of our common stock as reported on Nasdaq:

On September 7, 2018, the last reported sale price of our common stock on Nasdaq was $19.95 per share. As of August 31, 2018, we had 60 holders of record of our common stock. The actual number of holders of common stock is greater than this number of record holders and includes stockholders who are beneficial owners, but whose shares are held in street name by brokers and nominees. The number of holders of record also does not include stockholders whose shares may be held in trust by other entities.

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Dividend policy

The holders of our common stock are entitled to receive dividends when and if declared by the Board of Directors out of legally available funds. The declaration and payment of dividends are subject to the sole discretion of our Board of Directors and depend upon our profitability, financial condition, capital needs, credit agreement restrictions, future prospects and other factors deemed relevant by the Board of Directors. The following table sets forth the dividends per share paid during the last two fiscal years and the first and second quarters of 2018:

On August 9, 2018, we declared a quarterly dividend of $0.07 per share of common stock for the quarter ended September 30, 2018, payable on September 17, 2018 to holders of record on September 3, 2018.

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Capitalization

The following table sets forth our cash and cash equivalents and capitalization as of June 30, 2018:

You should read this information in conjunction with the information provided in the sections titled “Use of proceeds” and our consolidated financial statements and related notes incorporated herein by reference.

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Material United States federal income and estate tax consequences to non-U.S. holders

The following is a summary of material United States federal income and estate tax consequences to a non-U.S. holder (as defined below) of the purchase, ownership and disposition of our common stock purchased in this offering. Except where noted, this summary deals only with common stock that is held as a capital asset within the meaning of Section 1221 of the Internal Revenue Code of 1986, as amended, or the Code.

A “non-U.S. holder” means any beneficial owner of our common stock (other than an entity treated as a partnership for United States federal income tax purposes) that is not for United States federal income tax purposes any of the following:

A modified definition of “non-U.S. holder” applies for United States federal estate tax purposes (as discussed below).

This summary is based upon provisions of the Code and United States Treasury regulations, rulings and judicial decisions, in each case in effect as of the date hereof. Those authorities may be changed or be subject to differing interpretations, perhaps retroactively, so as to result in United States federal income and estate tax consequences different from those summarized below and which may adversely affect a non-U.S. holder of our common stock. This summary does not address all aspects of United States federal income and estate taxes and does not deal with foreign, state, local or other tax considerations that may be relevant to you in light of your particular circumstances. In addition, it does not represent a detailed description of the United States federal income tax consequences applicable to you if you are subject to special treatment under the United States federal income tax laws (including, without limitation, if you are a United States expatriate or a “controlled foreign corporation”).

If an entity treated as a partnership for United States federal income tax purposes holds our common stock, the tax treatment of a partner will generally depend upon the status of the partner and the activities of the partnership. If you are a partner of a partnership holding our common stock, you should consult your own tax advisors.

If you are considering the purchase of our common stock, you should consult your own tax advisors concerning the particular United States federal income and estate tax consequences to you of the purchase, ownership and disposition of the common stock, as well as the consequences to you arising under the laws of any other taxing jurisdiction.

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Dividends

In the event that we make a distribution of cash or other property (other than certain pro rata distributions of our stock) in respect of our common stock, the distribution generally will be treated as a dividend for United States federal income tax purposes to the extent it is paid from our current or accumulated earnings and profits, as determined under United States federal income tax principles. Any portion of a distribution that exceeds our current and accumulated earnings and profits generally will be treated first as a return of capital, causing a reduction in the adjusted tax basis of your common stock (but not below zero), and to the extent the amount of the distribution exceeds your adjusted tax basis in our common stock, the excess will be treated as gain from the disposition of our common stock (the tax treatment of which is discussed below under “—Gain on Disposition of Common Stock”).

Dividends paid to you generally will be subject to withholding of United States federal income tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty. However, dividends that are effectively connected with the conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, are attributable to a United States permanent establishment) are not subject to the withholding tax, provided that you must provide a properly executed Internal Revenue Service Form W-8ECI (or other applicable form) in accordance with the applicable certification requirements in order to establish an exemption from this withholding. Instead, such dividends are subject to United States federal income tax on a net-income basis generally in the same manner as if you were a United States person as defined under the Code. Any such effectively connected dividends received by a foreign corporation may be subject to an additional “branch profits tax” at a 30% rate or such lower rate as may be specified by an applicable income tax treaty.

If you wish to claim the benefit of an applicable treaty rate and avoid backup withholding, as discussed below, for dividends, you will be required (a) to provide the applicable withholding agent with a properly executed Internal Revenue Service Form W-8BEN or Form W-8BEN-E (or other applicable form) certifying under penalty of perjury that you are not a United States person as defined under the Code and are eligible for treaty benefits or (b) if our common stock is held through certain foreign intermediaries, to satisfy the relevant certification requirements of applicable United States Treasury regulations. Special certification and other requirements apply to certain non-U.S. holders that are pass-through entities rather than corporations or individuals.

If you are eligible for a reduced rate of United States withholding tax pursuant to an income tax treaty, you may obtain a refund of any excess amounts withheld by timely filing an appropriate claim for refund with the Internal Revenue Service.

Gain on disposition of common stock

Subject to the discussion of backup withholding and FATCA below, any gain realized by you on the taxable disposition of our common stock generally will not be subject to United States federal income tax unless:

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A non-U.S. holder described in the first bullet point immediately above generally will be subject to tax on the net gain derived from the disposition in the same manner as if the non-U.S. holder were a United States person as defined under the Code. In addition, if any non-U.S. holder described in the first bullet point immediately above is a foreign corporation, the gain realized by such non-U.S. holder may be subject to an additional “branch profits tax” at a 30% rate or such lower rate as may be specified by an applicable income tax treaty. An individual non-U.S. holder described in the second bullet point immediately above generally will be subject to a flat 30% (or such lower rate as may be specified by an applicable income tax treaty) tax on the gain derived from the disposition, which gain may be offset by United States-source capital losses, even though the individual is not considered a resident of the United States.

Although there can be no assurance, we believe we are not and do not anticipate becoming a “United States real property holding corporation” for United States federal income tax purposes.

Non-U.S. Holders should consult their tax advisors regarding potentially applicable income tax treaties that may provide for different rules.

Federal estate tax

Our common stock that is owned (or treated as owned) by an individual who is not a citizen or resident of the United States (as specially defined for United States federal estate tax purposes) at the time of death will be included in his or her gross estate for United States federal estate tax purposes, unless an applicable estate tax treaty provides otherwise, and, therefore, may be subject to United States federal estate tax.

Information reporting and backup withholding

Distributions paid to you and the amount of tax withheld, if any, with respect to such distributions generally will be reported to the Internal Revenue Service. Copies of the information returns reporting such dividends and any withholding may also be made available to the tax authorities in the country in which the you reside under the provisions of an applicable income tax treaty or exchange of information agreement.

You may be subject to backup withholding on dividends paid to you unless you certify, on an applicable Internal Revenue Service Form W-8, under penalty of perjury that you are a non-U.S. person, or otherwise establish an exemption.

Information reporting and, depending on the circumstances, backup withholding generally will apply to the proceeds of a sale or other disposition of our common stock within the United States or conducted through certain United States-related financial intermediaries, unless the beneficial owner certifies, on an applicable Internal Revenue Service Form W-8, under penalty of perjury that it is a non-U.S. person, or otherwise establishes an exemption.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against a non-U.S. holder’s United States federal income tax liability provided the required information is timely furnished to the Internal Revenue Service.

Additional withholding requirements

Under Sections 1471 through 1474 of the Code (commonly referred to as “FATCA”), a 30% United States federal withholding tax may apply to any dividends paid on our common stock, and, for a disposition of our common stock occurring after December 31, 2018, the gross proceeds from such disposition, in each case paid to (i) a “foreign financial institution” (as defined by the Code to include, in addition to banks and traditional financial

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institutions, entities such as investment funds and certain holding companies) which does not provide sufficient documentation, typically on Internal Revenue Service Form W-8BEN-E, evidencing either (x) an exemption from FATCA, or (y) its compliance (or deemed compliance) with FATCA (which may alternatively be in the form of compliance with an intergovernmental agreement with the United States) in a manner that avoids withholding, or (ii) a “non-financial foreign entity” (as specifically defined in the Code) which does not provide sufficient documentation, typically on Internal Revenue Service Form W-8BEN-E, evidencing either (x) an exemption from FATCA, or (y) adequate information regarding certain substantial United States beneficial owners of such entity (if any). Accordingly, entities through which our common stock is held may affect the determination of whether such withholding is required. If a dividend payment is both subject to withholding under FATCA and subject to the withholding tax discussed above under “—Dividends,” the withholding under FATCA may be credited against, and therefore reduce, such other withholding tax. The FATCA withholding tax will apply to all withholdable payments, however, without regard to whether the beneficial owner of the payment would otherwise be entitled to an exemption from imposition of withholding tax pursuant to an applicable tax treaty with the United States or U.S. domestic law. You should consult your own tax advisors regarding these requirements and whether they may be relevant to your ownership and disposition of our common stock.

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Underwriting (conflicts of interest)

The Company and the underwriters named below have entered into an underwriting agreement with respect to the shares being offered. Subject to certain conditions, each underwriter has severally agreed to purchase the number of shares indicated in the following table. J.P. Morgan Securities LLC is acting as representative of the underwriters.

The underwriters are committed to take and pay for all of the shares being offered, if any are taken, other than the shares covered by the option described below unless and until this option is exercised.

The underwriters have an option to buy up to an additional 1,875,000 shares from the Company. They may exercise that option for 30 days. If any shares are purchased pursuant to this option, the underwriters will severally purchase shares in approximately the same proportion as set forth in the table above.

The following table shows the per share and total underwriting discounts and commissions to be paid to the underwriters by the Company. Such amounts are shown assuming both no exercise and full exercise of the underwriters’ option to purchase 1,875,000 additional shares.

We estimate that our total expenses of the offering, excluding underwriting discounts and commissions, will be approximately $            . We have agreed to reimburse the underwriters for any filing fees incident to, and the reasonable and documented fees and disbursements of counsel in connection with, any required reviews by the Financial Industry Regulatory Authority, Inc. (“FINRA”) of the terms of the offering.

Shares sold by the underwriters to the public will initially be offered at the initial public offering price set forth on the cover of this prospectus. Any shares sold by the underwriters to securities dealers may be sold at a discount of up to $                 per share from the initial public offering price. After the initial offering of the shares, the representative may change the offering price and the other selling terms. The offering of the shares by the underwriters is subject to receipt and acceptance and subject to the underwriters’ right to reject any order in whole or in part. Sales of shares made outside of the United States may be made by affiliates of the underwriters.

A prospectus in electronic format may be made available on the web sites maintained by one or more underwriters, or selling group members, if any, participating in the offering. The underwriters may agree to allocate a number of shares to underwriters and selling group members for sale to their online brokerage account holders. Internet distributions will be allocated by the representative to underwriters and selling group members that may make Internet distributions on the same basis as other allocations.

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We, our directors and executive officers have agreed with the underwriters, for a period of 90 days after the date of this prospectus supplement, subject to certain exceptions, not to offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise dispose of any shares of common stock of the Company, or any options or warrants to purchase any shares of common stock of the Company, or any securities convertible into, exchangeable for or that represent the right to receive shares of common stock of the Company, without the prior written consent of J.P. Morgan Securities LLC. These restrictions do not prohibit sales by our Chief Executive Officer, Richard D. Holder, of up to 100,000 shares of common stock, our Chief Financial Officer, Thomas C. Burwell, Jr., of up to 34,000 shares of common stock, a member of our Board of Directors, and the Non-Executive Chairman of our Board of Directors, Robert E. Brunner, of up to 7,300 shares of common stock pursuant to trading plans established pursuant to Rule 10b5-1 under the Exchange Act entered into prior to the date of this prospectus supplement.

In connection with the offering, the underwriters may purchase and sell shares of common stock in the open market. These transactions may include short sales, stabilizing transactions and purchases to cover positions created by short sales. Short sales involve the sale by the underwriters of a greater number of shares than they are required to purchase in the offering, and a short position represents the amount of such sales that have not been covered by subsequent purchases. A “covered short position” is a short position that is not greater than the amount of additional shares for which the underwriters’ option described above may be exercised. The underwriters may cover any covered short position by either exercising their option to purchase additional shares or purchasing shares in the open market. In determining the source of shares to cover the covered short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase additional shares pursuant to the option described above. “Naked” short sales are any short sales that create a short position greater than the amount of additional shares for which the option described above may be exercised. The underwriters must cover any such naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the common stock in the open market after pricing that could adversely affect investors who purchase in the offering. Stabilizing transactions consist of various bids for or purchases of common stock made by the underwriters in the open market prior to the completion of the offering.

The underwriters may also impose a penalty bid. This occurs when a particular underwriter repays to the underwriters a portion of the underwriting discount received by it because the representative has repurchased shares sold by or for the account of such underwriter in stabilizing or short covering transactions.

Purchases to cover a short position and stabilizing transactions, as well as other purchases by the underwriters for their own accounts, may have the effect of preventing or retarding a decline in the market price of the Company’s stock, and together with the imposition of the penalty bid, may stabilize, maintain or otherwise affect the market price of the common stock. As a result, the price of the common stock may be higher than the price that otherwise might exist in the open market. The underwriters are not required to engage in these activities and may end any of these activities at any time. These transactions may be effected on Nasdaq, in the over-the-counter market or otherwise.

In addition, in connection with this offering, certain of the underwriters (and selling group members) may engage in passive market making transactions in the Company’s common stock on Nasdaq prior to the pricing and completion of this offering. Passive market making consists of displaying bids on Nasdaq no higher than the bid prices of independent market makers and making purchases at prices no higher than these independent bids and effected in response to order flow. Net purchases by a passive market maker on each day are generally limited to a specified percentage of the passive market maker’s average daily trading volume in our common stock during a specified period and must be discontinued when such limit is reached. Passive market making

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may cause the price of our common stock to be higher than the price that otherwise would exist in the open market in the absence of these transactions. If passive market making is commenced, it may be discontinued at any time.

Affiliates of some or all of the underwriters are lenders and, in some cases, some of the underwriters and/or their affiliates are agents, arrangers and/or book-running managers, under the Second Lien Facility. Net proceeds of this offering will be used to repay a portion of the borrowings outstanding under the Second Lien Facility. Because affiliates of some or all of the underwriters are lenders under the Second Lien Facility, to the extent that net proceeds of this offering are applied to repay borrowings under the Second Lien Facility, such affiliates will receive a portion of the net proceeds of this offering through the repayment of those borrowings. The aggregate amount of any such repayments received by any individual underwriter or its affiliates will, in the case of one or more underwriters, exceed 5% of the net proceeds of this offering (not including the underwriting discount). Therefore, this offering will be conducted in accordance with Rule 5121 of FINRA. None of the underwriters affiliated with a lender receiving 5% or more of the net proceeds of this offering will confirm sales of the Company’s common stock to accounts over which it exercises discretionary authority without the prior written consent of the customer.

In addition, the underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include sales and trading, commercial and investment banking, advisory, investment management, investment research, principal investment, hedging, market making, brokerage and other financial and non-financial activities and services. Certain of the underwriters and their respective affiliates have provided, and may in the future provide, a variety of these services to the issuer and to persons and entities with relationships with the issuer, for which they received or will receive customary fees and expenses.

In the ordinary course of their various business activities, the underwriters and their respective affiliates, officers, directors and employees may purchase, sell or hold a broad array of investments and actively trade securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments for their own account and for the accounts of their customers, and such investment and trading activities may involve or relate to assets, securities and/or instruments of the issuer (directly, as collateral securing other obligations or otherwise) and/or persons and entities with relationships with the issuer. The underwriters and their respective affiliates may also communicate independent investment recommendations, market color or trading ideas and/or publish or express independent research views in respect of such assets, securities or instruments and may at any time hold, or recommend to clients that they should acquire, long and/or short positions in such assets, securities and instruments.

We have agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act of 1933.

Other than in the United States, no action has been taken by us or the underwriters that would permit a public offering of the securities offered by this prospectus supplement in any jurisdiction where action for that purpose is required. The securities offered by this prospectus supplement may not be offered or sold, directly or indirectly, nor may this prospectus supplement or any other offering material or advertisements in connection with the offer and sale of any such securities be distributed or published in any jurisdiction, except under circumstances that will result in compliance with the applicable rules and regulations of that jurisdiction. Persons into whose possession this prospectus supplement comes are advised to inform themselves about and to observe any restrictions relating to the offering and the distribution of this prospectus supplement. This prospectus supplement does not constitute an offer to sell or a solicitation of an offer to buy any securities offered by this prospectus supplement in any jurisdiction in which such an offer or a solicitation is unlawful.

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European economic area

In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a “Relevant Member State”), with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State, no offer of shares may be made to the public in that Relevant Member State other than:

provided that no such offer of shares shall require the Company or any representative to publish a prospectus pursuant to Article 3 of the Prospectus Directive or supplement a prospectus pursuant to Article 16 of the Prospectus Directive and each person who initially acquires any shares or to whom any offer is made will be deemed to have represented, acknowledged and agreed to and with each of the representative and the Company that it is a “qualified investor” within the meaning of the law in that Relevant Member State implementing Article 2(1)(e) of the Prospectus Directive.

In the case of any shares being offered to a financial intermediary as that term is used in Article 3(2) of the Prospectus Directive, each such financial intermediary will be deemed to have represented, acknowledged and agreed that the shares acquired by it in the offer have not been acquired on a non-discretionary basis on behalf of, nor have they been acquired with a view to their offer or resale to, persons in circumstances which may give rise to an offer of any shares to the public other than their offer or resale in a Relevant Member State to qualified investors as so defined or in circumstances in which the prior consent of the representative has been obtained to each such proposed offer or resale.

For the purposes of this provision, the expression an “offer of shares to the public” in relation to any shares in any Relevant Member State means the communication in any form and by means of sufficient information on the terms of the offer and the shares to be offered so as to enable an investor to decide to purchase such shares, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State, the expression “Prospectus Directive” means Directive 2003/71/EC (as amended, including by Directive 2010/73/EU), and includes any relevant implementing measure in the Relevant Member State.

United Kingdom

In addition, in the United Kingdom, this document is being distributed only to, and is directed only at, and any offer subsequently made may only be directed at persons who are “qualified investors” (as defined in the Prospectus Directive) (i) who have professional experience in matters relating to investments falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the “Order”) and/or (ii) who are high net worth companies (or persons to whom it may otherwise be lawfully communicated) falling within Article 49(2)(a) to (d) of the Order (all such persons together being referred to as “relevant persons”) or otherwise in circumstances which have not resulted and will not result in an offer to the public of the shares in the United Kingdom within the meaning of the Financial Services and Markets Act 2000.

Any person in the United Kingdom that is not a relevant person should not act or rely on the information included in this document or use it as basis for taking any action. In the United Kingdom, any investment or investment activity that this document relates to may be made or taken exclusively by relevant persons.

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Canada

The shares may be sold in Canada only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the shares must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

Switzerland

The shares may not be publicly offered in Switzerland and will not be listed on the SIX Swiss Exchange (“SIX”) or on any other stock exchange or regulated trading facility in Switzerland. This document does not constitute a prospectus within the meaning of, and has been prepared without regard to the disclosure standards for issuance prospectuses under art. 652a or art. 1156 of the Swiss Code of Obligations or the disclosure standards for listing prospectuses under art. 27 ff. of the SIX Listing Rules or the listing rules of any other stock exchange or regulated trading facility in Switzerland. Neither this document nor any other offering or marketing material relating to the shares or the offering may be publicly distributed or otherwise made publicly available in Switzerland.

Neither this document nor any other offering or marketing material relating to the offering, the Company, the shares have been or will be filed with or approved by any Swiss regulatory authority. In particular, this document will not be filed with, and the offer of shares will not be supervised by, the Swiss Financial Market Supervisory Authority FINMA, and the offer of shares has not been and will not be authorized under the Swiss Federal Act on Collective Investment Schemes (“CISA”). The investor protection afforded to acquirers of interests in collective investment schemes under the CISA does not extend to acquirers of shares.

United Arab Emirates

The shares have not been, and are not being, publicly offered, sold, promoted or advertised in the United Arab Emirates (including the Dubai International Financial Centre) other than in compliance with the laws of the United Arab Emirates (and the Dubai International Financial Centre) governing the issue, offering and sale of securities. Further, this prospectus does not constitute a public offer of securities in the United Arab Emirates (including the Dubai International Financial Centre) and is not intended to be a public offer. This prospectus has not been approved by or filed with the Central Bank of the United Arab Emirates, the Securities and Commodities Authority or the Dubai Financial Services Authority.

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Australia

This prospectus supplement:

The shares may not be directly or indirectly offered for subscription or purchased or sold, and no invitations to subscribe for or buy the shares may be issued, and no draft or definitive offering memorandum, advertisement or other offering material relating to any shares may be distributed in Australia, except where disclosure to investors is not required under Chapter 6D of the Corporations Act or is otherwise in compliance with all applicable Australian laws and regulations. By submitting an application for the shares, you represent and warrant to us that you are an Exempt Investor.

As any offer of shares under this document will be made without disclosure in Australia under Chapter 6D.2 of the Corporations Act, the offer of those securities for resale in Australia within 12 months may, under section 707 of the Corporations Act, require disclosure to investors under Chapter 6D.2 if none of the exemptions in section 708 applies to that resale. By applying for the shares you undertake to us that you will not, for a period of 12 months from the date of issue of the shares, offer, transfer, assign or otherwise alienate those securities to investors in Australia except in circumstances where disclosure to investors is not required under Chapter 6D.2 of the Corporations Act or where a compliant disclosure document is prepared and lodged with ASIC.

Japan

The shares have not been and will not be registered pursuant to Article 4, Paragraph 1 of the Financial Instruments and Exchange Act. Accordingly, none of the shares nor any interest therein may be offered or sold, directly or indirectly, in Japan or to, or for the benefit of, any “resident” of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to or for the benefit of a resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the Financial Instruments and Exchange Act and any other applicable laws, regulations and ministerial guidelines of Japan in effect at the relevant time.

Hong Kong

The shares have not been offered or sold and will not be offered or sold in Hong Kong, by means of any document, other than (a) to “professional investors” as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong and any rules made under that Ordinance; or (b) in other circumstances which do not result in the document being a “prospectus” as defined in the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32) of Hong Kong or which do not constitute an offer to the public within the meaning of that

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Ordinance. No advertisement, invitation or document relating to the shares has been or may be issued or has been or may be in the possession of any person for the purposes of issue, whether in Hong Kong or elsewhere, which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to shares which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” as defined in the Securities and Futures Ordinance and any rules made under that Ordinance.

Singapore

This prospectus supplement has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of shares may not be circulated or distributed, nor may the shares be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore (the “SFA”), (ii) to a relevant person pursuant to Section 275(1), or any person pursuant to Section 275(1A), and in accordance with the conditions specified in Section 275 of the SFA, or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where the shares are subscribed or purchased under Section 275 of the SFA by a relevant person which is:

Securities (as defined in Section 239(1) of the SFA) of that corporation or the beneficiaries’ rights and interest (howsoever described) in that trust shall not be transferred within six months after that corporation or that trust has acquired the shares pursuant to an offer made under Section 275 of the SFA except:

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Legal matters

Certain legal matters, including the legality of the securities offered, will be passed upon for us by Bass, Berry & Sims, PLC, Memphis, Tennessee. The underwriters have been represented in this offering by Davis Polk & Wardwell LLP, New York, New York.

Experts

The financial statements of NN, Inc. and management’s assessment of the effectiveness of internal control over financial reporting (which is included in Management’s Report on Internal Control over Financial Reporting) incorporated in this prospectus supplement by reference to the Annual Report on Form 10-K of NN, Inc. for the year ended December 31, 2017, except as they relate to the financial statements of Wuxi Weifu Autocam Precision Machinery Co., Ltd. as of and for the year ended December 31, 2016, have been so incorporated in reliance on the report (which contains an adverse opinion on the effectiveness of internal control over financial reporting as of December 31, 2017) of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

The consolidated balance sheets of PMG Intermediate Holding Corporation and Subsidiaries as of December 31, 2017 and the related consolidated statements of income, comprehensive income, stockholders’ equity, and cash flows for the year then ended, included in this prospectus, have been so included in reliance on the report of RSM US LLP, independent auditors, given on the authority of that firm as experts in auditing and accounting.

Where you can find more information

We have filed a registration statement on Form S-3 with respect to the common stock offered by this prospectus supplement with the SEC. This prospectus supplement is a part of the registration statement and does not contain all of the information set forth in the registration statement and its exhibits and schedules, portions of which have been omitted as permitted by the rules and regulations of the SEC. For further information about us and our common stock, you should refer to the registration statement and its exhibits and schedules.

We are subject to the informational reporting requirements of the Exchange Act and, in accordance with the Exchange Act, we file annual, quarterly and special reports and other information with the SEC. Our filings with the SEC are available to the public on the SEC’s website at http://www.sec.gov. Those filings are also available to the public on, or accessible through, our website under the heading “Investors.” The information we file with the SEC or contained on or accessible through our corporate website or any other website that we may maintain is not part of this prospectus supplement, the accompanying prospectus or the registration statement of which this prospectus supplement is a part. You may also read and copy, at SEC prescribed rates, any document we file with the SEC, including the registration statement (and its exhibits) of which this prospectus supplement is a part, at the SEC’s Public Reference Room located at 100 F Street, N.E., Washington D.C. 20549. You can call the SEC at 1-800-SEC-0330 to obtain information on the operation of the Public Reference Room.

Incorporation by reference

The SEC’s rules allow us to “incorporate by reference” information into this prospectus supplement. This means that we can disclose important information to you by referring you to another document. Any information referred to in this way is considered part of this prospectus supplement from the date we file that document. Any reports filed by us pursuant to Sections 13(a), 13(c), 14 and 15 of the Exchange Act with the SEC after the date of this prospectus supplement and prior to the termination of this offering shall be deemed to be

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incorporated by reference in this prospectus supplement and to be a part hereof from the date of filing of such documents and, where applicable, supersede any information contained in this prospectus supplement or incorporated by reference in this prospectus supplement.

We incorporate by reference into this prospectus supplement the following documents or information filed with the SEC:

For purposes of the registration statement of which the accompanying prospectus is a part, any statement contained in a document incorporated or deemed to be incorporated herein by reference shall be deemed to be modified or superseded to the extent that a statement contained herein modifies or supersedes such statement in such document. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of the registration statement of which the accompanying prospectus is a part.

We also incorporate by reference any future filings we make with the SEC (other than information furnished pursuant to Item 2.02 or Item 7.01 of Form 8-K or as otherwise permitted by the SEC’s rules) under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act, until we have sold all of the shares of common stock to which this prospectus supplement relates or the offering is otherwise terminated.

You may obtain a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:

NN, Inc.

6210 Ardrey Kell Road

Charlotte, North Carolina 28277

(980) 264-4300

Attention: Secretary

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference.

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PROSPECTUS

NN, INC.

$400,000,000

Debt Securities

Preferred Stock

Common Stock

Warrants

Units

From time to time, we may sell up to an aggregate of $400,000,000 of any combination of the securities described in this prospectus. We will specify the terms of any offering of securities by us in a prospectus supplement.

You should read this prospectus, any prospectus supplement and the information incorporated by reference herein or therein carefully before you invest.

Investing in our securities involves a high degree of risk. You should carefully consider the risk factors described in the applicable prospectus supplement and certain of our filings with the Securities and Exchange Commission, as described under “Risk Factors” on page 3.

This prospectus may not be used to offer or sell any securities unless accompanied by a prospectus supplement.

Our common stock is quoted and traded on The NASDAQ Global Select Market under the ticker symbol “NNBR.” On March 13, 2017, the last reported sale price of our common stock on The NASDAQ Global Select Market was $22.45. The applicable prospectus supplement will contain information, where applicable, as to any other listing on The NASDAQ Global Select Market or any securities market or exchange of the securities covered by the prospectus supplement.

The securities may be offered directly by us to investors, to or through underwriters or dealers or through agents. If any underwriters are involved in the sale of any securities offered by this prospectus and any prospectus supplement, their names, and any applicable purchase price, fee, commission or discount arrangement between or among them, and any applicable options to purchase additional securities, will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement. The price to the public of such securities and the net proceeds we expect to receive from such sale will also be set forth in a prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is April 19, 2017.

Table of Contents

No person has been authorized to give any information or make any representations in connection with this offering other than those contained or incorporated by reference in this prospectus and any accompanying prospectus supplement in connection with the offering described in this prospectus and any accompanying prospectus supplement, and, if given or made, such information or representations must not be relied upon as having been authorized by us. Neither this prospectus nor any prospectus supplemental shall constitute an offer to sell or a solicitation of an offer to buy offered securities in any jurisdiction in which it is unlawful for such person to make such an offering or solicitation. Neither the delivery of this prospectus or any prospectus supplement nor any sale made hereunder shall under any circumstances imply that the information contained or incorporated by reference in this prospectus or in any prospectus supplement is correct as of any date subsequent to the date of this prospectus supplement or of any prospectus supplement.

Unless the context otherwise requires, all references to “NN,” “we,” “our,” “us” or “our company” in this prospectus refer to NN, Inc., a Delaware corporation and its consolidated subsidiaries.

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement filed with the Securities and Exchange Commission, or SEC, utilizing a shelf registration process. Under this shelf registration process, we may sell any combination of the securities described in this prospectus, either individually or in units, in one or more offerings, up to a total dollar amount of $400,000,000.

This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide a prospectus supplement that will contain specific information about the terms of that specific offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read this prospectus and the applicable prospectus supplement together with the additional information described under the heading “Where You Can Find More Information.”

DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS

Except for specific historical information, many of the matters discussed in this prospectus, or the information incorporated by reference into this prospectus, may express or imply projections of revenues or expenditures, statements of plans and objectives or future operations or statements of future economic performance. These, and similar statements, are forward-looking statements concerning matters that involve risks, uncertainties and other factors which may cause the actual performance of NN, Inc. and its subsidiaries to differ materially from those expressed or implied by this discussion. All forward-looking information appearing in this prospectus, including the information incorporated by reference into this prospectus, is provided by the company pursuant to the safe harbor established under the Private Securities Litigation Reform Act of 1995 and should be evaluated in the context of these factors. Forward-looking statements generally can be identified by the use of forward-looking terminology such as “assumptions”, “target”, “guidance”, “outlook”, “plans”, “projection”, “may”, “will”, “would”, “expect”, “intend”, “estimate”, “anticipate”, “believe”, “potential” or “continue” (or the negative or other derivatives of each of these terms) or similar terminology. Factors which could materially affect actual results include, but are not limited to, general economic conditions and economic conditions in the industrial sector, competitive influences, risks that current customers will commence or increase captive production, risks of capacity underutilization, quality issues, availability of raw materials, currency and other risks associated with international trade, our dependence on certain major customers, the impact of acquisitions and divestitures, unanticipated difficulties integrating acquisitions, new laws and governmental regulations, and other risk factors and cautionary statements listed from time-to-time in our periodic reports filed with the SEC. We caution readers not to place undue reliance upon any such forward-looking statements, which speak only as of the date made and are based on our beliefs, assumptions and estimates using information available to us at the time and are not intended to be guarantees of future events or performances.

For additional information concerning such risk factors and cautionary statements, please see the section titled “Risk Factors” in any prospectus supplement as well as in our Annual Report on Form 10-K for the fiscal year ended December 31, 2016 and our other reports on file with the SEC. Except as required by law, we undertake no obligation to update or revise any forward-looking statements we make in our prospectus, whether as a result of new information, future events or otherwise.

1

ABOUT NN, INC.

We are a diversified industrial company and a leading global manufacturer of high precision bearing components, industrial plastic products and precision metal components to a variety of markets on a global basis. We have 40 manufacturing plants in North America, Western Europe, Eastern Europe, South America and China.

We were incorporated in Delaware in October, 1980. Our principal executive offices are maintained at 207 Mockingbird Lane, Johnson City, Tennessee 37604 and our telephone number is (423) 434-8300. Our common stock is listed on The NASDAQ Global Select Market under the ticker symbol “NNBR.”

For further discussion of the material elements of our business, please refer to our Annual Report on Form 10-K for the fiscal year ended December 31, 2016 on file with the SEC, and any subsequent reports we file with the SEC, including those incorporated by reference into this prospectus.

2

RISK FACTORS

Investing in our securities involves a high degree of risk. Please see the risk factors under the heading “Risk Factors” in any prospectus supplement as well as in our Annual Report on Form 10-K for the fiscal year ended December 31, 2016 on file with the SEC, which are incorporated by reference into this prospectus and which may be amended, supplemented or superseded from time to time by other reports that we subsequently file with the SEC. Before you invest in our securities, you should carefully consider these risks as well as other information we include or incorporate by reference into this prospectus and the applicable prospectus supplement. The risks and uncertainties we have described are not the only ones facing our company. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business operations. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities. The discussion of risks includes or refers to forward-looking statements; you should read the explanation of the qualifications and limitations on such forward-looking statements discussed elsewhere in this prospectus.

USE OF PROCEEDS

Unless indicated otherwise in the applicable prospectus supplement, we expect to use the net proceeds for our operations and for other general corporate purposes, including, but not limited to, capital expenditures, repayment or refinancing of borrowings, working capital, investments and acquisitions. We have not allocated any portion of the net proceeds for any particular use at this time. Pending such uses, we may invest the net proceeds in demand deposits, money market accounts or short-term, investment-grade, interest-bearing securities or guaranteed obligations of the United States government or other securities. Additional information on the use of net proceeds may be set forth in the applicable prospectus supplement or other offering material relating to such offering. If net proceeds from a specific offering will be used to repay indebtedness, the applicable prospectus supplement or other offering material will describe the relevant terms of the debt to be repaid.

RATIO OF EARNINGS TO FIXED CHARGES

The following table sets forth our ratio of earnings to fixed charges in each of the periods indicated. The ratios are calculated by dividing earnings by the fixed charges.

3

DESCRIPTION OF THE SECURITIES

We may offer, from time to time, in one or more offerings, up to $400,000,000 of the following securities:

The aggregate initial offering price of the offered securities that we may issue will not exceed $400,000,000. If we issue debt securities at a discount from their principal amount, then, for purposes of calculating the aggregate initial offering price of the offered securities issued under this prospectus, we will include only the initial offering price of the debt securities and not the principal amount of the debt securities.

This prospectus contains a summary of the general terms of the various securities that we may offer. The prospectus supplement relating to any particular securities offered will describe the specific terms of the securities, which may be in addition to or different from the general terms summarized in this prospectus. Because the summary in this prospectus and in any prospectus supplement does not contain all of the information that you may find useful, you should read the documents relating to the securities that are described in this prospectus or in any applicable prospectus supplement. Please read “Where You Can Find More Information” to find out how you can obtain a copy of those documents.

The applicable prospectus supplement will also contain the terms of a given offering, the initial offering price and our net proceeds. Where applicable, a prospectus supplement will also describe any material United States federal income tax consequences relating to the securities offered and indicate whether the securities offered are or will be quoted or listed on any quotation system or securities exchange.

4

DESCRIPTION OF DEBT SECURITIES

This prospectus describes the general terms and provisions of the debt securities we may issue. When we offer to sell a particular series of debt securities, we will describe the specific terms of the securities in a supplement to this prospectus, including any additional covenants or changes to existing covenants relating to such series. The prospectus supplement also will indicate whether the general terms and provisions described in this prospectus apply to a particular series of debt securities.

We may offer senior or subordinated debt securities. Each series of debt securities may have different terms. The senior debt securities will be issued under a senior indenture, dated as of or prior to the date of such issuance, between us and a trustee to be named in the senior indenture, as amended or supplemented from time to time. We will refer to any such indenture throughout this prospectus as the “senior indenture.” Any subordinated debt securities will be issued under a separate indenture, dated as of or prior to the date of such issuance, between us and a trustee to be named in the subordinated indenture, as amended or supplemented from time to time. We will refer to any such indenture throughout this prospectus as the “subordinated indenture” and to the trustee under the senior or subordinated indenture as the “trustee.” The senior indenture and the subordinated indenture are sometimes individually referred to in this prospectus as an “indenture” and collectively referred to in this prospectus as the “indentures.” The indentures will be subject to and governed by the Trust Indenture Act of 1939, as amended. We have included copies of the forms of the indentures as exhibits to our registration statement and they are incorporated into this prospectus by reference.

If we issue debt securities at a discount from their principal amount, then, for purposes of calculating the aggregate initial offering price of the offered securities issued under this prospectus, we will include only the initial offering price of the debt securities and not the principal amount of the debt securities.

We have summarized below the material provisions of the indentures and the debt securities, or indicated which material provisions will be described in the related prospectus supplement. The prospectus supplement relating to any particular securities offered will describe the specific terms of the debt securities, which may be in addition to or different from the general terms summarized in this prospectus. Because the summary in this prospectus and in any prospectus supplement does not contain all of the information that you may find useful, you should read the documents relating to the debt securities that are described in this prospectus or in any applicable prospectus supplement. Please read “Where You Can Find More Information” to find out how you can obtain a copy of those documents. Except as otherwise indicated, the terms of the indentures are identical. As used under this caption, the term “debt securities” includes the debt securities being offered by this prospectus and any other debt securities issued by us under the indentures.

Because this section is a summary of some of the terms of the indentures, it does not describe every aspect of the debt securities. You should read the applicable indentures for a complete description of their provisions and the definitions of the terms used in them, because the indentures, and not this description, will define your rights as a holder of debt securities.

General

The indentures:

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Unless we give you different information in the applicable prospectus supplement, the senior debt securities will be unsubordinated obligations and will rank equally with all of our other unsecured and unsubordinated indebtedness. Payments on the subordinated debt securities will be subordinated to the prior payment in full of all of our senior indebtedness, as described under “—Subordination” and in the applicable prospectus supplement.

Each indenture provides that we may, but need not, designate more than one trustee under an indenture. Any trustee under an indenture may resign or be removed and a successor trustee may be appointed to act with respect to the series of debt securities administered by the resigning or removed trustee. If two or more persons are acting as trustee with respect to different series of debt securities, each trustee shall be a trustee of a trust under the applicable indenture separate and apart from the trust administered by any other trustee. Except as otherwise indicated in this prospectus, any action described in this prospectus to be taken by each trustee may be taken by each trustee with respect to, and only with respect to, the one or more series of debt securities for which it is trustee under the applicable indenture.

The prospectus supplement for each offering will provide the following terms, where applicable:

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We may issue debt securities at a discount below their principal amount and provide for less than the entire principal amount thereof to be payable upon declaration of acceleration of the maturity of the debt securities. We refer to any such debt securities throughout this prospectus as “original issue discount securities.” The applicable prospectus supplement will describe the United States federal income tax consequences and other relevant considerations applicable to original issue discount securities.

We also may issue indexed debt securities. Payments of principal of, and premium and interest on, indexed debt securities are determined with reference to the rate of exchange between the currency or currency unit in which the debt security is denominated and any other currency or currency unit specified by us, to the relationship between two or more currencies or currency units or by other similar methods or formulas specified in the prospectus supplement.

Except as described under “—Merger, Consolidation or Sale of Assets” or as may be set forth in any prospectus supplement, the debt securities will not contain any provisions that (1) would limit our ability to incur indebtedness or (2) would afford holders of debt securities protection in the event of (a) a highly leveraged or similar transaction involving us, or (b) a change of control or reorganization, restructuring, merger or similar transaction involving us that may adversely affect the holders of the debt securities. In the future, we may enter into transactions, such as the sale of all or substantially all of our assets or a merger or consolidation, that may have an adverse effect on our ability to service our indebtedness, including the debt securities, by, among other things, substantially reducing or eliminating our assets.

Neither the New York State laws nor our governing instruments define the term “substantially all” as it relates to the sale of assets. Additionally, New York cases interpreting the term “substantially all” rely upon the facts and circumstances of each particular case. Consequently, to determine whether a sale of “substantially all” of our assets has occurred, a holder of debt securities must review the financial and other information that we have disclosed to the public.

We will provide you with more information in the applicable prospectus supplement regarding any deletions, modifications, or additions to the events of default or covenants that are described below, including any addition of a covenant or other provision providing event risk or similar protection.

Payment

Unless we give you different information in the applicable prospectus supplement, the principal of, and any premium, or make-whole amount, and interest on, any series of the debt securities will be payable at the corporate trust office of the trustee. We will provide you with the address of the trustee in the applicable prospectus supplement. We may also pay interest by mailing a check to the address of the person entitled to it as it appears in the applicable register for the debt securities or by wire transfer of funds to that person at an account maintained within the United States.

All monies that we pay to a paying agent or a trustee for the payment of the principal of, and any premium, or make-whole amount, or interest on, any debt security will be repaid to us if unclaimed at the end of two years

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after the obligation underlying payment becomes due and payable. After funds have been returned to us, the holder of the debt security may look only to us for payment, without payment of interest for the period which we hold the funds.

Denomination, Interest, Registration and Transfer

Unless otherwise described in the applicable prospectus supplement, the debt securities of any series will be issuable in denominations of $1,000 and integral multiples of $1,000.

Subject to the limitations imposed upon debt securities that are evidenced by a computerized entry in the records of a depository company rather than by physical delivery of a note, a holder of debt securities of any series may:

Every debt security surrendered for registration of transfer or exchange must be duly endorsed or accompanied by a written instrument of transfer satisfactory to the applicable trustee or transfer agent. Payment of a service charge will not be required for any registration of transfer or exchange of any debt securities, but we or the trustee may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith. If in addition to the applicable trustee, the applicable prospectus supplement refers to any transfer agent initially designated by us for any series of debt securities, we may at any time rescind the designation of any such transfer agent or approve a change in the location through which any such transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for such series. We may at any time designate additional transfer agents for any series of debt securities.

Neither we, nor any trustee, will be required to:

Merger, Consolidation or Sale of Assets

The indentures provide that we may consolidate with or sell, lease or convey all or substantially all of our assets to, or merge with or into, any other entity provided that:

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Covenants

Existence. Except as described under “—Merger, Consolidation or Sale of Assets,” the indentures require us to do or cause to be done all things necessary to preserve and keep in full force and effect our existence, rights and franchises. However, the indentures do not require us to preserve any right or franchise if we determine that any right or franchise is no longer desirable in the conduct of our business.

Provision of financial information. The indentures require us to (1) within 15 days of each of the respective dates by which we are required to file our annual reports, quarterly reports and other documents with the SEC, file with the trustee copies of the annual report, quarterly report and other documents that we file with the SEC under Section 13 or 15(d) of the Exchange Act; and (2) file with the trustee and the SEC any additional information, documents and reports regarding compliance by us with the conditions and covenants of the indentures, as required.

Payment of taxes and other claims. The subordinated indenture requires us to pay, discharge or cause to be paid or discharged, before they become delinquent (1) all taxes, assessments and governmental charges levied or imposed on us, our subsidiaries or our subsidiaries’ income, profits or property, and (2) all lawful claims for labor, materials and supplies which, if unpaid, might by law become a lien upon our property or the property of our subsidiaries. However, we will not be required to pay, discharge or cause to be paid or discharged any such tax, assessment, charge or claim whose amount, applicability or validity is being contested in good faith by appropriate proceedings.

Additional covenants. The applicable prospectus supplement may set forth any additional covenants of NN relating to any series of debt securities.

Events of Default, Notice and Waiver

Unless the applicable prospectus supplement states otherwise, when we refer to “events of default” as defined in the indentures with respect to any series of debt securities, we mean:

(1) having an aggregate principal amount of at least $30,000,000; or

(2) under which there may be issued, secured or evidenced any existing or later created indebtedness for money borrowed by us or our subsidiaries, if we are directly responsible or liable as obligor or guarantor, in each case, if the default results in the indebtedness becoming or being declared due and payable prior to the date it otherwise would have, without such indebtedness having been discharged, or such acceleration having been rescinded or annulled, within 30 days after notice to the issuing company specifying such default. Such notice shall be given to us by the trustee, or to us and the trustee by the holders of at least 10% in principal amount of the outstanding debt securities of that series. The written notice specifying such default and requiring us to cause such indebtedness to be discharged or cause such acceleration to be rescinded or annulled and shall state that such notice is a “Notice of Default” under such indenture;

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When we use the term “significant subsidiary,” we refer to the meaning ascribed to such term in Rule 1-02 of Regulation S-X promulgated under the Securities Act.

If an event of default occurs and is continuing with respect to debt securities of any series outstanding, then the applicable trustee or the holders of 25% or more in principal amount of the debt securities of that series will have the right to declare the principal amount of all the debt securities of that series to be due and payable. If the debt securities of that series are original issue discount securities or indexed securities, then the applicable trustee or the holders of 25% or more in principal amount of the debt securities of that series will have the right to declare the portion of the principal amount as may be specified in the terms thereof to be due and payable. However, at any time after such a declaration of acceleration has been made, but before a judgment or decree for payment of the money due has been obtained by the applicable trustee, the holders of at least a majority in principal amount of outstanding debt securities of such series or of all debt securities then outstanding under the applicable indenture may rescind and annul such declaration and its consequences if:

The indentures also provide that the holders of at least a majority in principal amount of the outstanding debt securities of any series or of all debt securities then outstanding under the applicable indenture may, on behalf of all holders, waive any past default with respect to such series and its consequences, except a default:

The indentures require each trustee to give notice to the holders of debt securities within 90 days of a default unless such default has been cured or waived. However, the trustee may withhold notice if specified persons of such trustee consider such withholding to be in the interest of the holders of debt securities. The trustee may not withhold notice of a default in the payment of principal, any premium or interest on any debt security of such series or in the payment of any sinking fund installment in respect of any debt security of such series.

The indentures provide that holders of debt securities of any series may not institute any proceedings, judicial or otherwise, with respect to such indenture or for any remedy under the indenture, unless the trustee fails to act for a period of 60 days after the trustee has received a written request to institute proceedings in respect of an event of default from the holders of 25% or more in principal amount of the outstanding debt securities of such series, as well as an offer of indemnity reasonably satisfactory to the trustee. However, this provision will not prevent any holder of debt securities from instituting suit for the enforcement of payment of the principal of, and any premium, or make-whole amount, and interest on, such debt securities at the respective due dates thereof.

The indentures provide that, subject to provisions in each indenture relating to its duties in the case of a default, a trustee has no obligation to exercise any of its rights or powers at the request or direction of any holders of any

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series of debt securities then outstanding under the indenture, unless the holders have offered to the trustee reasonable security or indemnity. The holders of at least a majority in principal amount of the outstanding debt securities of any series or of all debt securities then outstanding under an indenture shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the applicable trustee, or of exercising any trust or power conferred upon such trustee. However, a trustee may refuse to follow any direction which:

Within 120 days after the close of each fiscal year, we will be required to deliver to each trustee a certificate, signed by one of our several specified officers, stating whether or not that officer has knowledge of any default under the applicable indenture. If the officer has knowledge of any default, the notice must specify the nature and status of the default.

Modification of the Indentures

We and our respective trustee may make modifications and amendments of an indenture without the consent of any holder of debt securities for any of the following purposes:

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The indentures provide that other modifications and amendments may be made only with the consent of the affected holders of at least a majority in principal amount of all outstanding affected debt securities issued under that indenture. However, no such modification or amendment may, without the consent of the holders of the debt securities affected by the modification or amendment:

The holders of a majority in aggregate principal amount of the outstanding debt securities of each series may, on behalf of all holders of debt securities of that series, waive, insofar as that series is concerned, our compliance with material restrictive covenants of the applicable indenture.

Voting

The indentures provide that in determining whether the holders of the requisite principal amount of outstanding debt securities of a series have given any request, demand, authorization, direction, notice, consent or waiver under the indentures or whether a quorum is present at a meeting of holders of debt securities:

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The indentures contain provisions for convening meetings of the holders of debt securities of a series. A meeting will be permitted to be called at any time by the applicable trustee, and also, upon request, by us or the holders of at least 25% in principal amount of the outstanding debt securities of such series, in any such case upon notice given as provided in such indenture. Except for any consent that must be given by the holder of each debt security affected by the modifications and amendments of an indenture described above, any resolution presented at a meeting or adjourned meeting duly reconvened at which a quorum is present may be adopted by the affirmative vote of the holders of a majority of the aggregate principal amount of the outstanding debt securities of that series represented at such meeting.

Notwithstanding the preceding paragraph, except as referred to above, any resolution relating to a request, demand, authorization, direction, notice, consent, waiver or other action that may be made, given or taken by the holders of a specified percentage, which is less than a majority of the aggregate principal amount of the outstanding debt securities of a series, may be adopted at a meeting or adjourned meeting duly reconvened at which a quorum is present by the affirmative vote of such specified percentage.

Any resolution passed or decision taken at any properly held meeting of holders of debt securities of any series will be binding on all holders of such series. The quorum at any meeting called to adopt a resolution, and at any reconvened meeting, will be persons holding or representing a majority in principal amount of the outstanding debt securities of a series. However, if any action is to be taken relating to a consent or waiver which may be given by the holders of at least a specified percentage in principal amount of the outstanding debt securities of a series, the persons holding such percentage will constitute a quorum.

Notwithstanding the foregoing provisions, the indentures provide that if any action is to be taken at a meeting with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that such indenture expressly provides may be made, given or taken by the holders of a specified percentage in principal amount of all outstanding debt securities affected by such action, or of the holders of such series and one or more additional series:

Subordination

Unless otherwise provided in the applicable prospectus supplement, subordinated debt securities will be subject to the following subordination provisions.

Upon any distribution to our creditors in a liquidation, dissolution or reorganization, the payment of the principal of and interest on any subordinated debt securities will be subordinated to the extent provided in the applicable indenture in right of payment to the prior payment in full of all senior debt. However, our obligation to make payments of the principal of and interest on such subordinated debt securities otherwise will not be affected. No payment of principal or interest will be permitted to be made on subordinated debt securities at any time if a default on senior debt exists that permits the holders of such senior debt to accelerate its maturity and the default is the subject of judicial proceedings or we receive notice of the default. After all senior debt is paid in full and until the subordinated debt securities are paid in full, holders of subordinated debt securities will be subrogated to the rights of holders of senior debt to the extent that distributions otherwise payable to holders of subordinated debt securities have been applied to the payment of senior debt. The subordinated indenture will not restrict the amount of senior debt or other indebtedness of NN and its subsidiaries. As a result of these subordination provisions, in the event of a distribution of assets upon insolvency, holders of subordinated debt securities may recover less, ratably, than our general creditors.

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The term “senior debt” will be defined in the applicable indenture as the principal of and interest on, or substantially similar payments to be made by us in respect of, other outstanding indebtedness, whether outstanding at the date of execution of the applicable indenture or subsequently incurred, created or assumed. The prospectus supplement may include a description of additional terms implementing the subordination feature.

No restrictions will be included in any indenture relating to subordinated debt securities upon the creation of additional senior debt.

If this prospectus is being delivered in connection with the offering of a series of subordinated debt securities, the accompanying prospectus supplement or the information incorporated in this prospectus by reference will set forth the approximate amount of senior debt outstanding as of the end of our most recent fiscal quarter.

Discharge, Defeasance and Covenant Defeasance

Unless otherwise indicated in the applicable prospectus supplement, the indentures allow us to discharge our obligations to holders of any series of debt securities issued under any indenture when:

Unless otherwise indicated in the applicable prospectus supplement, the indentures provide that, upon our irrevocable deposit with the applicable trustee, in trust, of an amount, in such currency or currencies, currency unit or units or composite currency or currencies in which such debt securities are payable at stated maturity, or government obligations, or both, applicable to such debt securities, which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay the principal of, and any premium, or make-whole amount, and interest on, such debt securities, and any mandatory sinking fund or analogous payments thereon, on the scheduled due dates therefor, the issuing company may elect either:

Notwithstanding the above, we may not elect to defease and be discharged from the obligation to pay any additional amounts upon the occurrence of particular events of tax, assessment or governmental charge with respect to payments on such debt securities and the obligations to register the transfer or exchange of such debt securities, to replace temporary or mutilated, destroyed, lost or stolen debt securities, to maintain an office or agency in respect of such debt securities, or to hold monies for payment in trust.

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The indentures only permit us to establish the trust described in the paragraph above if, among other things, it has delivered to the applicable trustee an opinion of counsel to the effect that the holders of such debt securities will not recognize income, gain or loss for United States federal income tax purposes as a result of such defeasance or covenant defeasance and will be subject to United States federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such defeasance or covenant defeasance had not occurred. Such opinion of counsel, in the case of defeasance, will be required to refer to and be based upon a ruling received from or published by the Internal Revenue Service or a change in applicable United States federal income tax law occurring after the date of the indenture. In the event of such defeasance, the holders of such debt securities would be able to look only to such trust fund for payment of principal, any premium, or make-whole amount, and interest.

When we use the term “government obligations,” we mean securities that are:

However, except as required by law, such custodian is not authorized to make any deduction from the amount payable to the holder of such depository receipt from any amount received by the custodian in respect of the government obligation or the specific payment of interest on or principal of the government obligation evidenced by such depository receipt.

Unless otherwise provided in the applicable prospectus supplement, if after we have deposited funds and/or government obligations to effect defeasance or covenant defeasance with respect to debt securities of any series, (1) the holder of a debt security of such series is entitled to, and does, elect under the terms of the applicable indenture or the terms of such debt security to receive payment in a currency, currency unit or composite currency other than that in which such deposit has been made in respect of such debt security, or (2) a conversion event occurs in respect of the currency, currency unit or composite currency in which such deposit has been made, the indebtedness represented by such debt security will be deemed to have been, and will be, fully discharged and satisfied through the payment of the principal of, and premium, or make-whole amount, and interest on, such debt security as they become due out of the proceeds yielded by converting the amount so deposited in respect of such debt security into the currency, currency unit or composite currency in which such debt security becomes payable as a result of such election or such cessation of usage based on the applicable market exchange rate.

When we use the term “conversion event,” we mean the cessation of use of:

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Unless otherwise provided in the applicable prospectus supplement, all payments of principal of, and any premium, or make-whole amount, and interest on, any debt security that is payable in a foreign currency that ceases to be used by its government of issuance shall be made in United States dollars.

In the event that (1) we effect covenant defeasance with respect to any debt securities, and (2) those debt securities are declared due and payable because of the occurrence of any event of default, the amount in the currency, currency unit or composite currency in which such debt securities are payable, and government obligations on deposit with the applicable trustee, will be sufficient to pay amounts due on such debt securities at the time of their stated maturity but may not be sufficient to pay amounts due on such debt securities at the time of the acceleration resulting from such event of default. However, the issuing company would remain liable to make payments of any amounts due at the time of acceleration.

The applicable prospectus supplement may further describe the provisions, if any, permitting such defeasance or covenant defeasance, including any modifications to the provisions described above, with respect to the debt securities of or within a particular series.

Conversion Rights

The terms and conditions, if any, upon which the debt securities are convertible into common stock or preferred stock will be set forth in the applicable prospectus supplement. The terms will include whether the debt securities are convertible into shares of common stock or preferred stock, the conversion price, or manner of calculation thereof, the conversion period, provisions as to whether conversion will be at the issuing company’s option or the option of the holders, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption of the debt securities and any restrictions on conversion.

Global Securities

The debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depository identified in the applicable prospectus supplement relating to such series. Global securities, if any, issued in the United States are expected to be deposited with The Depository Trust Company, or DTC, as depository. We may issue global securities in either registered or bearer form and in either temporary or permanent form. We will describe the specific terms of the depository arrangement with respect to a series of debt securities in the applicable prospectus supplement relating to such series. We expect that unless the applicable prospectus supplement provides otherwise, the following provisions will apply to depository arrangements.

Once a global security is issued, the depository for such global security or its nominee will credit on its book-entry registration and transfer system the respective principal amounts of the individual debt securities represented by such global security to the accounts of participants that have accounts with such depository. Such accounts shall be designated by the underwriters, dealers or agents with respect to such debt securities or by us if we offer such debt securities directly. Ownership of beneficial interests in such global security will be limited to participants with the depository or persons that may hold interests through those participants.

We expect that, under procedures established by DTC, ownership of beneficial interests in any global security for which DTC is the depository will be shown on, and the transfer of that ownership will be effected only through, records maintained by DTC or its nominee, with respect to beneficial interests of participants with the depository, and records of participants, with respect to beneficial interests of persons who hold through participants with the depository. Neither we nor the trustee will have any responsibility or liability for any aspect of the records of DTC or for maintaining, supervising or reviewing any records of DTC or any of its participants relating to beneficial ownership interests in the debt securities. The laws of some states require that certain purchasers of securities take physical delivery of such securities in definitive form. Such limits and laws may impair the ability to own, pledge or transfer beneficial interest in a global security.

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So long as the depository for a global security or its nominee is the registered owner of such global security, such depository or such nominee, as the case may be, will be considered the sole owner or holder of the debt securities represented by the global security for all purposes under the applicable indenture. Except as described below or in the applicable prospectus supplement, owners of beneficial interest in a global security will not be entitled to have any of the individual debt securities represented by such global security registered in their names, will not receive or be entitled to receive physical delivery of any such debt securities in definitive form and will not be considered the owners or holders thereof under the applicable indenture. Beneficial owners of debt securities evidenced by a global security will not be considered the owners or holders thereof under the applicable indenture for any purpose, including with respect to the giving of any direction, instructions or approvals to the trustee under the indenture. Accordingly, each person owning a beneficial interest in a global security with respect to which DTC is the depository must rely on the procedures of DTC and, if such person is not a participant with the depository, on the procedures of the participant through which such person owns its interests, to exercise any rights of a holder under the applicable indenture. We understand that, under existing industry practice, if DTC requests any action of holders or if an owner of a beneficial interest in a global security desires to give or take any action which a holder is entitled to give or take under the applicable indenture, DTC would authorize the participants holding the relevant beneficial interest to give or take such action, and such participants would authorize beneficial owners through such participants to give or take such actions or would otherwise act upon the instructions of beneficial owners holding through them.

Payments of principal of, and any premium, or make-whole amount, and interest on, individual debt securities represented by a global security registered in the name of a depository or its nominee will be made to or at the direction of the depository or its nominee, as the case may be, as the registered owner of the global security under the applicable indenture. Under the terms of the applicable indenture, we and the trustee may treat the persons in whose name debt securities, including a global security, are registered as the owners thereof for the purpose of receiving such payments. Consequently, neither we nor the trustee have or will have any responsibility or liability for the payment of such amounts to beneficial owners of debt securities including principal, any premium, or make-whole amount, or interest. We believe, however, that it is currently the policy of DTC to immediately credit the accounts of relevant participants with such payments, in amounts proportionate to their respective holdings of beneficial interests in the relevant global security as shown on the records of DTC or its nominee. We also expect that payments by participants to owners of beneficial interests in such global security held through such participants will be governed by standing instructions and customary practices, as is the case with securities held for the account of customers in bearer form or registered in street name, and will be the responsibility of such participants.

Redemption notices with respect to any debt securities represented by a global security will be sent to the depository or its nominee. If less than all of the debt securities of any series are to be redeemed, we expect the depository to determine the amount of the interest of each participant in such debt securities to be redeemed to be determined by lot. Neither we, the trustee, any paying agent nor the security registrar for such debt securities will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in the global security for such debt securities or for maintaining any records with respect thereto.

Neither we nor the trustee will be liable for any delay by the holders of a global security or the depository in identifying the beneficial owners of debt securities, and we and the trustee may conclusively rely on, and will be protected in relying on, instructions from the holder of a global security or the depository for all purposes. The rules applicable to DTC and its participants are on file with the SEC.

If a depository for any debt securities is at any time unwilling, unable or ineligible to continue as depository and we do not appoint a successor depository within 90 days, we will issue individual debt securities in exchange for the global security representing such debt securities. In addition, we may at any time and in our sole discretion, subject to any limitations described in the applicable prospectus supplement relating to such debt securities, determine not to have any of such debt securities represented by one or more global securities and in such event

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will issue individual debt securities in exchange for the global security or securities representing such debt securities. Individual debt securities so issued will be issued in denominations of $2,000 and integral multiples of $1,000.

The debt securities of a series may also be issued in whole or in part in the form of one or more bearer global securities that will be deposited with a depository, or with a nominee for such depository, identified in the applicable prospectus supplement. Any such bearer global securities may be issued in temporary or permanent form. The specific terms and procedures, including the specific terms of the depositary arrangement, with respect to any portion of a series of debt securities to be represented by one or more bearer global securities will be described in the applicable prospectus supplement.

No Recourse

There is no recourse under any obligation, covenant or agreement in the applicable indenture or with respect to any security against any of our or our successor’s past, present or future stockholders, employees, officers or directors.

DESCRIPTION OF PREFERRED STOCK

Our certificate of incorporation authorizes our board of directors, without stockholder approval, to designate and issue up to 5,000,000 shares of preferred stock, par value $.01 per share, in one or more series and to fix the rights, preferences, privileges and restrictions granted to or imposed upon each such series of preferred stock, including voting rights, dividend rights, conversion rights, terms of redemption, liquidation preference, sinking fund terms, subscription rights and the number of shares constituting any series or the designation of a series. Our board of directors can issue, without stockholder approval, preferred stock with voting and conversion rights that could adversely affect the voting power of the holders of common stock and reduce the likelihood that such holders will receive dividend payments or payments upon liquidation. Such issuance could have the effect of decreasing the market price of the common stock. The issuance of preferred stock or even the ability to issue preferred stock could also have the effect of delaying, deterring or preventing a change of control or other corporate action.

We also have authority to issue 200,000 shares of Series A preferred stock, par value $.01 per share, all of which shares are designated as “Series A Junior Participating Preferred Stock.” The powers, preferences, rights, qualifications, limitations and restrictions of shares of our preferred stock and our Series A preferred stock have been fixed in amendments to our certificate of incorporation. As of March 10, 2017, no shares of preferred stock or Series A preferred stock were issued and outstanding.

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DESCRIPTION OF COMMON STOCK

The following is a description of the material terms and provisions of our common stock. It may not contain all the information that is important to you. You can access complete information by referring to our certificate of incorporation and bylaws.

General

Under our certificate of incorporation, we have authority to issue 45,000,000 shares of common stock, par value $.01 per share. As of March 10, 2017, there were 27,302,846 shares of common stock issued and outstanding. All shares of common stock will, when issued, be duly authorized, fully paid and nonassessable. Thus, the full price for the outstanding shares of common stock will have been paid at issuance and any holder of our common stock will not be later required to pay us any additional money for such common stock.

Dividends

Subject to preferential rights of any other class or series of preferred stock, holders of common stock may receive dividends pro rata out of assets that we can legally use to pay dividends, when, as and if they are declared by our board of directors. In the event we are liquidated, dissolved or our affairs are wound up, after we pay or make adequate provision for all of our known debts and liabilities, each holder of common stock will receive dividends pro rata out of assets that we can legally use to pay distributions, subject to any rights that are granted to the holders of any class or series of preferred stock.

Voting Rights

Holders of common stock will have the exclusive power to vote on all matters presented to our stockholders, including the election of directors, except as otherwise provided by Delaware law or as provided with respect to any other class or series of stock. Holders of common stock are entitled to one vote per share. There is no cumulative voting in the election of our directors, which means that, subject to any rights to elect directors that are granted to the holders of any class or series of preferred stock, a majority of the votes cast at a meeting of stockholders at which a quorum is present is required to elect a director in any uncontested election and a plurality of the votes cast at a meeting of stockholders at which a quorum is present is required to elect a director in any contested election.

Other Rights

Subject to the preferential rights of any other class or series of preferred stock, all shares of common stock have equal dividend, distribution, liquidation and other rights, and have no preference, appraisal or exchange rights, except for any appraisal rights provided by Delaware law. Furthermore, holders of common stock have no conversion, sinking fund or redemption rights, or preemptive rights to subscribe for any of our securities.

Delaware Anti-Takeover Statute

We are subject to the provisions of Section 203 of the General Corporation Law of the State of Delaware regulating corporate takeovers. In general, Section 203, subject to certain exceptions, prohibits a publicly-held Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years following the date that such person or entity became an interested stockholder, unless:

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The application of Section 203 may limit the ability of stockholders to approve a transaction that they may deem to be in their best interests. In addition, Section 203 makes it more difficult for an interested stockholder to effect various business combinations with a corporation for a three-year period, although the stockholders may, by adopting an amendment to our certificate of incorporation or bylaws, elect not to be governed by this section, effective 12 months after adoption.

In general, Section 203 defines “business combination” as:

In general, Section 203 defines an “interested stockholder” as any person that is:

Our certificate of incorporation and bylaws do not exclude us from the restrictions imposed under Section 203. We anticipate that the provisions of Section 203 may encourage companies interested in acquiring us to negotiate in advance with our board of directors because the stockholder approval requirement would be avoided if a majority of the directors then in office approve either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder.

Classified Board and Other Matters

Our board of directors is divided into three classes, each of which serves until the third annual meeting of shareholders after their election, with one class being elected each year. Subject to the preferential rights of any other class or series of preferred stock, any director, or the entire board of directors, may be removed from office at any time, with or without cause, by the affirmative vote of the holders of ta majority of the voting power of all the then outstanding shares of voting stock of the company, voting together as a single class. Our bylaws require that shareholders provide the Secretary of our company with notice of the nomination of a person for election as a director with respect to an election to be held at an annual meeting of stockholders, not less than 90 nor more than 120 days prior to the anniversary date of the immediately preceding annual meeting of stockholders or special meeting in lieu of an annual meeting, provided, however , that if the date of the annual meeting is more than 30 days before or more than 60 days after such anniversary date, notice by the stockholder to be timely must be given, not earlier than the 120th day prior to such annual meeting and not later than the 90th day prior to such annual meeting or, if later, the 10th day following the day on which public disclosure of the date of such annual

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meeting was first made. To be timely, a stockholder’s notice for nominations to be made at a special meeting must be made not earlier than the 120th day prior to such special meeting and not later than the 90th day prior to such special meeting or, if later, the 10th day following the day on which public disclosure of the date of such special meeting was first made. Our bylaws provide that special meetings of shareholders of our company may be called only by: (i) the Chairman of the board of directors, (ii) by a majority of the board of directors, or (iii) the Chief Executive Officer of our Company. Our certificate of incorporation, as well as applicable provisions of the General Corporation Law of the State of Delaware, provide that no action required or permitted to be taken at any annual or special meeting of our shareholders may be taken without a meeting, unless the consent of two-thirds of the voting power of the then outstanding shares of stock of the company entitled to vote on the matter is obtained. These provisions may diminish the likelihood that a potential acquiror would make an offer for our common stock or that there would otherwise be a change in control of our company.

Transfer Agent

The transfer agent and registrar for our common stock is Computershare Trust Company, N.A.

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DESCRIPTION OF WARRANTS

We have no warrants outstanding. We may issue warrants for the purchase of preferred stock, common stock or debt securities. Warrants may be issued independently, together with any other securities offered by any prospectus supplement or through a dividend or other distribution to our stockholders and may be attached to or separate from such securities. We may issue warrants under a warrant agreement to be entered into between us and a warrant agent. We will name any warrant agent in the applicable prospectus supplement. The warrant agent will act solely as our agent in connection with the warrants of a particular series and will not assume any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants.

The following is a description of the general terms and provisions of any warrants we may issue and may not contain all the information that is important to you. You can access complete information by referring to the applicable prospectus supplement. In the applicable prospectus supplement, we will describe the terms of the warrants and applicable warrant agreement, including, where applicable, the following:

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DESCRIPTION OF UNITS

This section outlines some of the provisions of the units and the unit agreements. This information may not be complete in all respects and is qualified entirely by reference to the unit agreement with respect to the units of any particular series. The specific terms of any series of units will be described in the applicable prospectus supplement. If so described in a particular supplement, the specific terms of any series of units may differ from the general description of terms presented below.

We may issue units comprised of shares of preferred stock, shares of common stock, warrants and debt securities in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date.

The applicable prospectus supplement may describe:

The provisions described in this section, as well as those described under “Description of Debt Securities,” “Description of Preferred Stock,” “Description of Common Stock” and “Description of Warrants” will apply to the securities included in each unit, to the extent relevant.

Issuance in Series

We may issue units in such amounts and in as many distinct series as we wish. This section summarizes terms of the units that apply generally to all series. Most of the financial and other specific terms of your series will be described in the applicable prospectus supplement.

Unit Agreements

We will issue the units under one or more unit agreements to be entered into between us and a bank or other financial institution, as unit agent. We may add, replace or terminate unit agents from time to time. We will identify the unit agreement under which each series of units will be issued and the unit agent under that agreement in the applicable prospectus supplement.

The following provisions will generally apply to all unit agreements unless otherwise stated in the applicable prospectus supplement.

Modification Without Consent

We and the applicable unit agent may amend any unit or unit agreement without the consent of any holder:

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We do not need any approval to make changes that affect only units to be issued after the changes take effect. We may also make changes that do not adversely affect a particular unit in any material respect, even if they adversely affect other units in a material respect. In those cases, we do not need to obtain the approval of the holder of the unaffected unit; we need only obtain any required approvals from the holders of the affected units.

Modification With Consent

We may not amend any particular unit or a unit agreement with respect to any particular unit unless we obtain the consent of the holder of that unit, if the amendment would:

Any other change to a particular unit agreement and the units issued under that agreement would require the following approval:

These provisions regarding changes with majority approval also apply to changes affecting any securities issued under a unit agreement, as the governing document.

In each case, the required approval must be given by written consent.

Mergers and Similar Transactions Permitted; No Restrictive Covenants or Events of Default

The unit agreements will not restrict our ability to merge or consolidate with, or sell our assets to, another corporation or other entity or to engage in any other transactions. If at any time we merge or consolidate with, or sell our assets substantially as an entirety to, another corporation or other entity, the successor entity will succeed to and assume our obligations under the unit agreements. We will then be relieved of any further obligation under these agreements.

The unit agreements will not include any restrictions on our ability to put liens on our assets, including our interests in our subsidiaries, nor will they restrict our ability to sell our assets. The unit agreements also will not provide for any events of default or remedies upon the occurrence of any events of default.

Governing Law

The unit agreements and the units will be governed by New York law.

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Form, Exchange and Transfer

We will issue each unit in global form only (i.e., book-entry). Units in book-entry form will be represented by a global security registered in the name of a depositary, which will be the holder of all the units represented by the global security. Those who own beneficial interests in a unit will do so through participants in the depositary’s system, and the rights of these indirect owners will be governed solely by the applicable procedures of the depositary and its participants. We will describe book-entry securities, and other terms regarding the issuance and registration of the units in the applicable prospectus supplement.

Each unit and all securities comprising the unit will be issued in the same form.

If we issue any units in registered, non-global form, the following will apply to them.

The units will be issued in the denominations stated in the applicable prospectus supplement. Holders may exchange their units for units of smaller denominations or combined into fewer units of larger denominations, as long as the total amount is not changed.

Only the depositary will be entitled to transfer or exchange a unit in global form, since it will be the sole holder of the unit.

Payments and Notices

In making payments and giving notices with respect to our units, we will follow the procedures as described in the applicable prospectus supplement.

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PLAN OF DISTRIBUTION

We may sell the securities in any one or more of the following methods from time to time:

The distribution of the securities may be effected from time to time in one or more transactions:

Any of the prices may represent a discount from the prevailing market prices.

An offering may be on a best efforts or a firm commitment basis. If underwriters are used in the sale, the securities acquired by the underwriters will be for their own accounts. The underwriters may resell the securities in one or more transactions, including without limitation, negotiated transactions, at a fixed public offering price or at a varying price determined at the time of sale. The obligations, if any, of the underwriter to purchase any securities will be subject to certain conditions. We may offer the securities to the public through underwriting syndicates represented by managing underwriters or by underwriters without a syndicate. Subject to certain conditions, the underwriters will be obligated to purchase all of the securities if any are purchased, other than securities covered by any option to purchase additional securities. Any public offering price and any discounts or concessions allowed, reallowed or paid to dealers may be changed from time to time.

If a dealer is used in an offering of securities, we may sell the securities to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of sale.

We may sell securities directly or through agents we designate from time to time. We will name any agent involved in the offering and sale of securities and we will describe any commissions we will pay the agent in the prospectus supplement. Unless the prospectus supplement states otherwise, our agent will act on a best-efforts basis for the period of its appointment.

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We may also sell securities directly to one or more purchasers without using underwriters, dealers or agents.

We may also make direct sales through subscription rights distributed to our stockholders on a pro rata basis, which may or may not be transferable. In any distribution of subscription rights to stockholders, if all of the underlying securities are not subscribed for, we may then sell the unsubscribed securities directly to third parties or may engage the services of one or more underwriters, dealers or agents, including standby underwriters, to sell the unsubscribed securities to third parties.

In the sale of the securities, underwriters, dealers or agents may receive compensation from us or from purchasers of the securities, for whom they may act as agents, in the form of discounts, concessions or commissions. Underwriters may sell the securities to or through dealers, and such dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agents. Underwriters, dealers and agents that participate in the distribution of the securities may be deemed to be underwriters under the Securities Act and any discounts or commissions they receive from us and any profit on the resale of securities they realize may be deemed to be underwriting discounts and commissions under the Securities Act. The applicable prospectus supplement will, where applicable:

Unless otherwise specified in the related prospectus supplement, each series of securities will be a new issue with no established trading market, other than the common stock, which is listed on The NASDAQ Global Select Market under the symbol “NNBR”. Any common stock sold pursuant to a prospectus supplement will be listed on The NASDAQ Global Select Market, subject to applicable notices. We may elect to apply for quotation or listing of any other class or series of our securities, on a quotation system or an exchange but we are not obligated to do so.

Any underwriter may engage in over-allotment, stabilizing transactions, short covering transactions and penalty bids in accordance with Regulation M under the Exchange Act. Over-allotment involves sales in excess of the offering size which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum price in accordance with Rule 104 of Regulation M. Short covering transactions involve purchases of the securities in the open market after the distribution is completed to cover short positions. Short covering transactions also may be effected through a partial or full over-allotment exercise granted to them by us. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a covering transaction to cover short positions. Those activities may cause the price of the securities to be higher than it would otherwise be. The underwriters are not obligated to conduct any of these activities and if commenced, the underwriters may discontinue any of the activities at any time. Therefore, no assurance can be given as to the liquidity of, or the trading market for, any other class or series of our securities.

Any underwriters who are qualified market makers on the NASDAQ Global Select Market may engage in passive market making transactions in the securities on the NASDAQ Global Select Market in accordance with

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Rule 103 of Regulation M under the Exchange Act during the business day prior to the pricing of the offering and before the commencement of offers or sales of the securities. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security; if all independent bids are lowered below the passive market maker’s bid, however, the passive market maker’s bid must then be lowered when certain purchase limits are exceeded.

We may sell the securities in exchange in whole or part for consideration other than cash. This consideration may consist of services or products, whether tangible or intangible, and including services or products we may use in our business; outstanding debt or equity securities of our company or one or more of its subsidiaries; debt or equity securities or assets of other companies, including in connection with investments, joint ventures or other strategic transactions, or acquisitions; release of claims or settlement of disputes; and satisfaction of obligations, including obligations to make payments to distributors or other suppliers and payment of interest on outstanding obligations. We may sell the securities as part of a transaction in which outstanding debt or equity securities of our company or one or more of our subsidiaries are surrendered, converted, exercised, canceled or transferred.

We do not make any representation or prediction as to the direction or magnitude of any effect that the transactions described above might have on the price of the securities. In addition, we do not make any representation that underwriters will engage in such transactions or that such transactions, once commenced, will not be discontinued without notice at any time.

Under agreements into which we may enter, underwriters, dealers and agents who participate in the distribution of the securities may be entitled to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, or contribution from us to payments which the underwriters, dealers or agents may be required to make.

Some of the underwriters, dealers and agents and their affiliates may engage in transactions with or perform services for us and our affiliates in the ordinary course of business. Underwriters have from time to time in the past, and may from time to time in the future, provide investment banking services to us for which they have in the past received, and in the future may receive, customary fees.

If indicated in the applicable prospectus supplement, securities may also be offered or sold by a “remarketing firm” in connection with a remarketing arrangement contemplated by the terms of the securities. Remarketing firms may act as principals for their own accounts or as agents. The applicable prospectus supplement will identify any remarketing firm and the terms of its agreement, if any, with us. It will also describe the remarketing firms compensation. Remarketing firms may be deemed to be underwriters in connection with the remarketing of the securities.

If indicated in the applicable prospectus supplement, we will authorize underwriters, dealers or other persons acting as our agents to solicit offers by particular institutions to purchase securities from us at the public offering price set forth in such prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on such future date or dates stated in such prospectus supplement. Each delayed delivery contract will be for an amount no less than, and the aggregate principal amounts of securities sold under delayed delivery contracts shall be not less nor more than, the respective amounts stated in the applicable prospectus supplement. Institutions with which such delayed delivery contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and others, but will in all cases be subject to our approval. The obligations of any purchaser under any such contract will be subject to the conditions that (1) the purchase of the securities shall not at the time of delivery be prohibited under the laws of any jurisdiction in the United States to which the purchaser is subject, and (2) if the securities are being sold to underwriters, we shall have sold to the underwriters the total principal amount of the securities less the principal amount thereof covered by the delayed delivery contracts. The underwriters and such other agents will not have any responsibility in respect of the validity or performance of such delayed delivery contracts.

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To comply with applicable state securities laws, the securities offered by this prospectus will be sold, if necessary, in such jurisdictions only through registered or licensed brokers or dealers. In addition, securities may not be sold in some states unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

INFORMATION INCORPORATED BY REFERENCE

The SEC allows us to incorporate by reference the information and reports we file with it, which means that we can disclose important information to you by referring you to these documents. Our SEC file number is 000-23486. The information incorporated by reference is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede the information already incorporated by reference. We are incorporating by reference the documents listed below, which we have already filed with the SEC, and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to termination to the offering of the securities described in this prospectus except as to any portion of any future report or document that is deemed furnished and not filed under such provisions:

Upon request, we will provide, without charge, to each person to whom a copy of this prospectus is delivered a copy of the documents incorporated by reference into this prospectus. You may request a copy of these filings, and any exhibits we have specifically incorporated by reference as an exhibit in this prospectus, at no cost by writing or telephoning us at the following address:

NN, Inc.

207 Mockingbird Lane

Johnson City, Tennessee 37604

(423) 434-8300

Attention: Matthew S. Heiter, Esq, Senior Vice President and General Counsel

This prospectus is part of a registration statement we filed with the SEC. We have incorporated exhibits into this registration statement. You should read the exhibits carefully for provisions that may be important to you.

You should rely only on the information incorporated by reference or provided in this prospectus or any prospectus supplement. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus or in the documents incorporated by reference is accurate as of any date other than the date on the front of this prospectus or those documents.

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WHERE YOU CAN FIND MORE INFORMATION

We are subject to the information requirements of the Exchange Act, and in accordance with the Exchange Act, file annual, quarterly and special reports, proxy statements and other information with the SEC. You may read and copy any document we file at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. You may call the SEC at 1-800-SEC-0330 for further information on the operation of the Public Reference Room. These documents also may be accessed through the SEC’s electronic data gathering, analysis and retrieval system, or EDGAR, via electronic means, including the SEC’s home page on the Internet ( www.sec.gov ). Our telephone number is (423) 434-8300. Our website is located at www.nninc.com. Information contained on our website, other than the documents that we file with the SEC that are incorporated by reference in this prospectus, is not incorporated by reference into this prospectus and, therefore, is not part of this prospectus or any accompanying prospectus supplement.

EXPERTS

The financial statements and management’s assessment of the effectiveness of internal control over financial reporting (which is included in Management’s Report on Internal Control over Financial Reporting) incorporated in this Prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2016 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

The consolidated financial statements of Autocam Corporation as of December 31, 2013 and 2012, and for each of the years in the three-year period ended December 31, 2013 incorporated in this Prospectus by reference from NN’s Amendment to Current Report on Form 8-K filed with the SEC on October 27, 2014, have been audited by Deloitte & Touche LLP, independent auditors, as stated in their report which is incorporated herein by reference. Such consolidated financial statements have been so incorporated in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.

The consolidated financial statements of Precision Engineered Products Holdings, Inc. at December 31, 2014 and 2013, and for each of the three years in the period ended December 31, 2014, incorporated by reference in this Prospectus and Registration Statement have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their report thereon appearing elsewhere herein, and are included in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

The financial statements of Wuxi Weifu Autocam Precision Machinery Company, Ltd. as of and for the year ended December 31, 2016 incorporated in this Prospectus by reference from NN’s Annual Report on Form 10-K filed with the SEC on March 16, 2017, have been audited by Deloitte Touche Tohmatsu Certified Public Accountants LLP, an independent registered public accounting firm, as stated in their report which is incorporated herein by reference. Such financial statements have been so incorporated by reference in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.

LEGAL MATTERS

Certain legal matters, including the legality of the securities offered, will be passed upon for us by Bass, Berry & Sims PLC, Memphis, Tennessee.

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12,500,000 shares

NN, Inc.

Common stock

Prospectus supplement

                , 2018