exv3w31

/s/ EDWARD J. COONEY

Edward J. Cooney

Vice President and Treasurer

Exhibit 3.31

AMENDED AND RESTATED
CERTIFICATE OF INCORPORATION

The name of the corporation is Huntair, Inc. This corporation’s original Certificate of Incorporation was filed with the Secretary of State of the State of Delaware on March 17, 2006 under the name Acquisition Sub 2006-2, Inc. This Amended and Restated Certificate of Incorporation was duly adopted in accordance with Sections 242 and 245 of the General Corporation Law of the State of Delaware (the “DGCL”), and restates, integrates and amends the provisions of this corporation’s Certificate of Incorporation.

The text of the Certificate of Incorporation is amended and restated as follows:

1. The name of this corporation is Huntair, Inc.

2. Its registered office in the State of Delaware is to be located at 2711 Centerville Road, Suite 400, in the City of Wilmington, County of New Castle and its registered agent at such address is CORPORATION SERVICE COMPANY.

3. The purpose or purposes of the corporation shall be:

To engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of Delaware.

4. The total number of shares of stock which this corporation shall have the authority to issue is 3,000 shares of common stock $0.01 par value per share. Each share of common stock shall be entitled to one vote.

5. The Corporation is to have perpetual existence.

6. Except as otherwise provided in the provisions establishing a class of stock, the number of authorized shares of any class or series of stock may be increased or decreased (but not below the number of shares thereof then outstanding) by the affirmative vote of the holders of a majority of the voting power of the corporation entitled to vote irrespective of the provisions of Section 242(b)(2) of the General Corporation Law of the State of Delaware.

7. The election of Directors need not be by written ballot unless the by-laws of the Corporation so provide.

8. In furtherance and not in limitation of the power conferred upon the board of directors by law, the board of directors shall have the power to make, adopt, alter, amend and repeal from time to time by-laws of this corporation, subject to the right of the stockholders entitled to vote with respect thereto to alter and repeal by-laws made by the board of directors.

9. No director shall be personally liable to the Corporation or its stockholders for monetary damages for any breach of fiduciary duty by such director as a director. Notwithstanding

the foregoing sentence, a director shall be liable to the extent provided by applicable law, (i) for breach of the director’s duty of loyalty to the Corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) pursuant to Section 174 of the Delaware General Corporation Law or (iv) for any transaction from which the director derived an improper personal benefit. No amendment to or repeal of this Article Seventh shall apply to or have any effect on the liability or alleged liability of any director of the Corporation for or with respect to any acts or omissions of such director occurring prior to such amendment.

10. This corporation shall, to the maximum extent permitted from time to time under the law of the State of Delaware, indemnify and upon request advance expenses to any person who is or was a party or is threatened to be made a party to any threatened, pending or completed action suit, proceeding or claim, whether civil, criminal, administrative or investigative, by reason of the fact that such person is or was or has agreed to be a director or officer of this corporation or while a director or officer is or was serving at the request of this corporation as a director, officer, partner, trustee, employee or agent of any corporation, partnership, joint venture, trust or other enterprise, including service with respect to employee benefit plans, against expenses (including attorney’s fees and expenses), judgments, fines, penalties and amounts paid in settlement incurred (and not otherwise recovered) in connection with the investigation, preparation to defend or defense of such action, suit, proceeding or claim; provided, however, that the foregoing shall not require this corporation to indemnify or advance expenses to any person in connection with any action, suit, proceeding, claim or counterclaim initiated by or on behalf of such person. Such indemnification shall not be exclusive of other indemnification rights arising under any by-law, agreement, vote of directors or stockholders or otherwise and shall inure to the benefit of the heirs and legal representatives of such person. Any person seeking indemnification under this paragraph 10 shall be deemed to have met the standard of conduct required for such indemnification unless the contrary shall be established. Any repeal or modification of the foregoing provisions of this paragraph 10 shall not adversely affect any right or protection of a director or officer of this corporation with respect to any acts or omissions of such director or officer occurring prior to such repeal or modification.

11. The books of this corporation may (subject to any statutory requirements) be kept outside the State of Delaware as may be designated by the board of directors or in the by-laws of this corporation.

IN WITNESS WHEREOF, the undersigned has executed signed and acknowledged this amended and restated certificate of incorporation this 17th day of December 2009.