Exhibit 3.1

CERTIFICATE OF INCORPORATION OF

STR HOLDINGS, INC.

FIRST:  The name of the Corporation is: STR Holdings, Inc.

SECOND:  The address of the registered office of the Corporation in the State of Delaware is Corporation Service Company, 2711 Centerville Road, Wilmington, County of New Castle, State of Delaware, 19808. The name of the registered agent of the Corporation in the State of Delaware at such address is Corporation Service Company.

THIRD:  The purpose of the Corporation is to engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of the State of Delaware, as from time to time amended (the “DGCL”).

FOURTH:  (a)  The total number of shares of all classes of stock which the Corporation shall have authority to issue is Two Hundred Twenty Million (220,000,000) shares, consisting of (a) Two Hundred Million (200,000,000) shares of Common Stock, par value $0.01 per share (“Common Stock”) and (b) Twenty Million (20,000,000) shares of one or more series of Preferred Stock, par value $0.01 per share (“Preferred Stock”).

(b)  Except as otherwise provided by law, the shares of stock of the Corporation, regardless of class, may be issued by the Corporation from time to time in such amounts, for such consideration and for such corporate purposes as the Board of Directors of the Corporation (the “Board of Directors”) may from time to time determine.

(c)  Shares of Preferred Stock may be issued from time to time in one or more series of any number of shares as may be determined from time to time by the Board of Directors, provided that the aggregate number of shares issued and not cancelled of any and all such series shall not exceed the total number of shares of Preferred Stock authorized by this Certificate of Incorporation.  Each series of Preferred Stock shall be distinctly designated.  The voting powers, if any, of each such series and the preferences and relative, participating, optional and other special rights of each such series and the qualifications, limitations and restrictions thereof, if any, may differ from those of any and all other series at any time outstanding; and the Board of Directors is hereby expressly granted authority to fix, in the resolution or resolutions providing for the issue of a particular series of Preferred Stock, the voting powers, if any, of each such series and the designations, preferences and relative, participating, optional and other special rights of each such series and the qualifications, limitations and restrictions thereof to the full extent now or hereafter permitted by this Certificate of Incorporation and the laws of the State of Delaware.  Shares of Preferred Stock, regardless of series, that are converted into other securities or other consideration or otherwise acquired by the Corporation shall be retired and cancelled, and the Corporation shall take all such actions as are necessary to cause such shares to have the status of authorized but unissued shares

of Preferred Stock, without designation as to series, and the Company shall have the right to reissue such shares.

(d)  Subject to the provisions of applicable law or of the Bylaws of the Corporation with respect to the closing of the transfer books or the fixing of a record date for the determination of stockholders entitled to vote, and except as otherwise provided by law or by the resolution or resolutions providing for the issue of any series of Preferred Stock, the holders of outstanding shares of Common Stock shall exclusively possess the voting power for the election of directors and for all other purposes, each holder of record of shares of Common Stock being entitled to one vote for each share of Common Stock standing in such holder’s name on the books of the Corporation.  Shares of capital stock of the Corporation shall not be entitled to cumulative voting.

(e)  Notwithstanding any other provisions of this Certificate of Incorporation or the Bylaws of the Corporation (and notwithstanding the fact that some lesser percentage may be specified by law, this Certificate of Incorporation or the Bylaws of the Corporation), any director or the entire Board of Directors of the Corporation may be removed from office for cause or without cause by the affirmative vote of the holders of outstanding shares of capital stock of the Corporation entitled to vote generally in the election of directors (considered for this purpose as one class) cast a meeting of the stockholders called for that purpose, the notice for which states that the purpose or one of the purposes of the meeting is the removal of such director, and constituting at least a majority of such shares entitled to vote if such removal is for cause, or at least 75% of such shares entitled to vote if such removal is without cause.  Notwithstanding the foregoing, and except as otherwise required by law, whenever the holders of any one or more series of Preferred Stock shall have the right, voting separately as a class, to elect one or more directors of the Corporation, the provisions of paragraph (e) of this Article shall not apply with respect to the director or directors elected by such holders of Preferred Stock.  For purposes of this Article Fourth, “cause” shall mean, with respect to any director, (i) the willful failure by such director to perform, or the gross negligence of such director in performing, the duties of a director, (ii) the engaging by such director in willful or serious misconduct that is injurious to the Corporation or (iii) the conviction of such director of, or the entering by such director of a plea of nolo contendere to, a crime that constitutes a felony.

FIFTH:  In furtherance and not in limitation of the powers conferred by law, subject to any limitations contained elsewhere in this Certificate of Incorporation, Bylaws of the Corporation may be adopted, amended or repealed by a majority of the Board of Directors of the Corporation, but any Bylaws adopted by the Board of Directors may be amended or repealed by the stockholders entitled to vote thereon.  Election of directors need not be conducted by written ballot.

SIXTH:  (a)  The number of directors of the Corporation shall be fixed from time to time exclusively by the Board of Directors pursuant to resolution adopted by a majority of the directors then in office; provided, however, that the number of directors shall not be less than three (3) nor more than fifteen (15).

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(b)  Any vacancies in the Board of Directors for any reason, and any directorships resulting from any increase in the number of directors, may be filled only by the Board of Directors (and not by the stockholders), acting by the affirmative vote of a majority of the remaining directors, although less than a quorum, or by a sole remaining director.  Any directors so chosen shall hold office until the next election of the class for which such directors shall have been chosen and until their successors shall be elected and shall qualify.  No decrease in the number of directors shall shorten the term of any incumbent director.

(c)  Notwithstanding the foregoing, whenever the holders of any one or more classes or series of Preferred Stock shall have the right, voting separately by class or series, to elect one or more directors at an annual or special meeting of stockholders, the election, terms of office, filling of vacancies, removal of directors and other features of the directorships shall be governed by the terms of this Certificate of Incorporation or in any resolution or resolutions adopted by the Board of Directors providing for the issuance of any class or series of Preferred Stock.

(d)  Advance notice of nominations for the election of directors, other than by the Board of Directors or a duly authorized committee thereof or any authorized officer of the Corporation to whom the Board of Directors or such committee shall have delegated such authority, and information concerning nominees, shall be given in the manner provided in the Bylaws of the Corporation.

SEVENTH:  A director of the Corporation shall not be personally liable either to the Corporation or to any stockholder for monetary damages for breach of fiduciary duty as a director, except (i) for any breach of the director’s duty of loyalty to the Corporation or its stockholders, (ii) for acts or omissions which are not in good faith or which involve intentional misconduct or knowing violation of law, (iii) for any matter in respect of which such director shall be liable under Section 174 of the DGCL or any amendment thereto or successor provision thereto, or (iv) for any transaction from which the director shall have derived an improper personal benefit.  Neither amendment nor repeal of this Article SEVENTH nor the adoption of any provision of the Certificate of Incorporation of the Corporation inconsistent with this Article SEVENTH shall eliminate or reduce the effect of this paragraph in respect of any matter occurring, or any cause of action, suit or claim that, but for this Article SEVENTH, would accrue or arise, prior to such amendment, repeal or adoption of an inconsistent provision.  If the DGCL is amended to eliminate or further limit the liability of directors, then the liability of a director of the Corporation, in addition to the limitation on personal liability provided herein, shall be limited to the fullest extent permitted by the DGCL.

EIGHTH.  Any action required or permitted to be taken by the stockholders of the Corporation may only be effected at a duly called annual or special meeting of the stockholders of the Corporation, and may not be effected by the stockholders in writing in lieu of such a meeting, unless such action by written consent of stockholders is unanimously recommended by the directors of the Corporation then in office.

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NINTH.  The Corporation shall not be governed by Section 203 of the DGCL (“Section 203”), and the restrictions contained in Section 203 shall not apply to the Corporation.

TENTH.  To the fullest extent permitted by Section 122(17) of the DGCL and except as may be otherwise expressly agreed in writing by the Corporation and DLJ Merchant Banking Partners IV, L.P. and its affiliates (collectively, “DLJMB”), the Corporation, on behalf of itself and its subsidiaries, renounces any interest or expectancy of the Corporation and its subsidiaries in, or in being offered an opportunity to participate in, business opportunities, which are from time to time presented to DLJMB or any of its officers, directors, agents, stockholders, members, partners, affiliates and subsidiaries (other than the Corporation and its subsidiaries), even if the opportunity is one that the Corporation or its subsidiaries might reasonably be deemed to have pursued or had the ability or desire to pursue if granted the opportunity to do so, and no such person shall be liable to the Corporation or any of its subsidiaries for breach of any fiduciary or other duty, as a director or officer or otherwise, by reason of the fact that such person pursues or acquires such business opportunity, directs such business opportunity to another person or fails to present such business opportunity, or information regarding such business opportunity, to the Corporation or its subsidiaries unless, in the case of any such person who is a director or officer of the Corporation, such business opportunity is expressly offered to such director or officer in writing solely in his or her capacity as a director or officer of the Corporation.  Any person purchasing or otherwise acquiring any interest in any shares of stock of the Corporation shall be deemed to have notice of and consented to the provisions of this Article TENTH.  Neither the alteration, amendment or repeal of this Article TENTH, nor the adoption of any provision of this Certificate of Incorporation inconsistent with this Article TENTH, shall eliminate or reduce the effect of this Article TENTH in respect of any business opportunity first identified or any other matter occurring, or any cause of action, suit or claim that, but for this Article TENTH, would accrue or arise, prior to such alteration, amendment, repeal or adoption.

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