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                                                                       Exhibit 3

                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                               MET-PRO CORPORATION


         FIRST. The name of the corporation is MET-PRO CORPORATION

         SECOND. Its principal office in the State of Delaware is located at No.
100 West Tenth Street, in the City of Wilmington, County of New Castle. The name
and address of its resident agent is The Corporation Trust Company, No. 100 West
Tenth Street, Wilmington 99, Delaware.

         THIRD. The nature of the business, or objects or purposes to be
transacted, promoted or carried on are:

         To design, manufacture, buy and sell and generally deal in equipment,
machinery, systems and devices for purifying and filtering water for home
consumption and for industrial and commercial use and for use of municipalities,
including the water to be used therein and to manufacture, buy and sell and
generally deal in equipment, machinery, systems and devices for purifying and
filtering liquids other than water and of gases (including air) of all kinds.

         To manufacture, purchase or otherwise acquire, invest in, own,
mortgage, pledge, sell assign and transfer or otherwise dispose of, trade, deal
in and deal with goods, wares and merchandise and personal property of every
class and description.

         To acquire, and pay for in cash, stock or bonds of this corporation or
otherwise, the goodwill, rights, assets and property, and to undertake or assume
the whole or any part of the obligations or liabilities of any person, firm,
association or corporation.

         To acquire, hold, use, sell, assign, lease, grant licenses in respect
of, mortgage or otherwise dispose of letters patent of the United States or any
foreign country, patent rights, licenses and privileges, inventions,
improvements and processes, copyrights, trademarks and trade names, relating to
or useful in connection with any business of this corporation.

         To acquire by purchase, subscription or otherwise, and to receive,
hold, own, guarantee, sell, assign, exchange, transfer, mortgage, pledge or
otherwise dispose of or deal in and with any of the shares of the capital stock,
or any voting trust certificates in respect of the shares of capital stock,
scrip, warrants, rights, bonds, debentures, notes, trust receipts, and other
securities, obligations, choses in action and evidences of indebtedness or
interest issued or created by any corporations, joint stock companies,
syndicates, associations, firms, trusts or persons, public or private, or by the
government of the United States of America, or by any foreign government, or by
any state, territory, province, municipality or other political subdivision or
by any governmental agency, and as owner thereof to possess and exercise all the
rights, powers and privileges of ownership, including the right to execute
consents and vote thereon, and to do any and all acts and things necessary or
advisable for the preservation, protection, improvement and enhancement in value
thereof.

         To enter into, make and perform contracts of every kind and description
with any person, firm, association, corporation, municipality, county, state,
body politic or government or colony or dependency thereof.

         To borrow or raise moneys for any of the purposes of the corporation
and, from time to time without limit as to amount, to draw, make, accept,
endorse, execute and issue promissory notes, drafts, bills of exchange,
warrants, bonds, debentures and other negotiable or non-negotiable instruments
and evidences of indebtedness, and to secure the payment of any thereof and of
the interest thereon by mortgage upon or pledge, conveyance or assignment in
trust of the whole or any part of the property of the corporation, whether at
the time owned or thereafter acquired, and to sell, pledge or otherwise dispose
of such bonds or other obligations of the corporation for its corporate
purposes.

         To loan to any person, firm or corporation any of its surplus funds,
either with or without security.

         To purchase, hold, sell and transfer the shares of its own capital
stock; provided it shall not use its funds or property for the purchase of its
own shares of capital stock when such use would cause any impairment of its
capital except as otherwise permitted by law, and provided further that shares
of its own capital stock belonging to it shall not be voted upon directly or
indirectly.

         To have one or more offices, to carry on all or any of its operations
and business and without restriction or limit as to amount to purchase or
otherwise acquire, hold, own, mortgage, sell, convey or otherwise dispose of
real and personal property of every class and description in any of the states,
districts, territories or colonies of the United States, and in any and all
foreign countries, subject to the laws of such state, districts, territory,
colony or country.


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         In general, to carry on any other business in connection with the
foregoing, and to have and exercise all the powers conferred by the laws of
Delaware upon corporations formed under the General Corporation Law of the State
of Delaware, and to do any or all of the things hereinbefore set forth to the
same extent as natural persons might or could do.

         The objects and purposes specified in the foregoing clauses shall,
except where otherwise expressed, be in nowise limited or restricted by
reference to, or inference from, the terms of any other clause in this
certificate of incorporation, but the objects and purposes specified in each of
the foregoing clauses of this article shall be regarded as independent objects
and purposes.

         FOURTH. The total number of shares of stock which the corporation shall
have authority to issue is Ten Million (10,000,000), each share to be designated
Common Stock and to have a par value of Ten Cents ($.10), amounting to aggregate
capital of One Million Dollars ($1,000,000).

         FIFTH. The minimum amount of capital with which the corporation will
commence business is One Thousand Dollars ($1,000.00).

         SIXTH. The names and places of residence of the incorporators are as
follows:
             NAMES                       RESIDENCES
             -----                       ----------
         S.H. Livesay               Wilmington, Delaware
         F.J. Obara, Jr.            Wilmington, Delaware
         A.D. Grier                 Wilmington, Delaware

         SEVENTH.  The corporation is to have perpetual existence.

         EIGHTH. The private property of the stockholders shall not be subject
to the payment of corporate debts to any extent whatever.

         NINTH. The following provisions are inserted for the management of the
business and for the conduct of the affairs of this corporation, and for further
definition, limitation and regulation of the powers of this corporation and of
its directors and stockholders:

         (1) The number of directors of the corporation shall be such as from
time to time shall be fixed by, or in the manner provided in the by-laws, but
shall not be less than three (3). Election of directors need not be by ballot
unless the by-laws so provide.

         (2) Vacancies among the directors and newly created directorships
resulting from an increase in the number of directors shall be filled in the
manner provided in the by-laws.

         (3)  The board of directors shall have power

         (a) Without the assent or vote of the stockholders to make, alter,
     amend, change, add to, or repeal the by-laws of this corporation; to fix
     and vary the amount to be reserved for any proper purpose; to authorize and
     cause to be executed mortgages and liens upon any part of the property of
     the corporation; to determine the use and disposition of any surplus or net
     profits and to fix the times for the declaration and payment of dividends.

         (b) To determine from time to time whether, and to what extent, and at
     what times and places, and under what conditions and regulations, the
     accounts and books of the corporations (other than the stock ledger) or any
     of them, shall be open to the inspection of the stockholders.

         (c) To designate one or more committees, each committee to consist of
     two or more of the directors of the corporation, which, to the extent
     provided in the resolution or in the by-laws of the corporation, shall have
     and may exercise the powers of the board of directors in the management of
     the business and affairs of the corporation, and may authorize the seal of
     the corporation to be affixed to all papers which may require it. Such
     committee or committees shall have such name or names as may be stated in
     the by-laws of the corporation or as may be determined from time to time by
     resolution adopted by the board of directors.

         (4) In addition to the powers and authorities hereinbefore or by
statute expressly conferred upon them, the directors are hereby empowered to
exercise all such powers and do all such acts as may be exercised or done by the
corporation; subject, nevertheless, to the provisions of the statutes of
Delaware, of this certificate and to any by-laws from time to time by the
stockholders; provided, however, that no by-law so made shall invalidate any
prior act of the directors which would have been valid if such by-law had not
been made.


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         (5) When and as authorized by the affirmative vote of the holders of a
majority of the stock issued and outstanding having voting power given at a
stockholders' meeting duly called for that purpose, or when authorized by the
written consent of the holders of a majority of the voting stock issued and
outstanding, to sell, lease, or exchange all of the property and assets of the
corporation, including its goodwill and its corporate franchises, upon such
terms and conditions and for such consideration, which may be in whole or in
part shares of stock in, and/or other securities of, any other corporation or
corporations, as its board of directors shall deem expedient and for the best
interests of the corporation.

         TENTH. In the absence of fraud, no contract or other transaction
between this corporation and any other person, firm, or corporation or any
partnership or association shall be effected or invalidated by the fact that any
director or officer of this corporation is pecuniarily or otherwise interested
in or is a director, member or officer of such other corporation or of such
person, firm, association or partnership or is a party to or is pecuniarily or
otherwise interested in such contract or other transaction or in any way
connected with any person or persons, firm, association, partnership or
corporation pecuniarily or otherwise interested therein; any director so
interested may be counted in determining the existence of a quorum at any
meeting of the board of directors of this corporation for the purpose of
authorizing any such contract or transaction with like force and effect as if he
were not so interested, or were not a director, member or officer of such other
corporation, firm, association or partnership. Any director whose interest in
any such contract or transaction arises solely by reason of the fact that he is
a stockholder, officer or creditor of such other corporation (or solely by
reason of the fact that he is a director of such other corporation or partner in
such firm where such dealing, contract or arrangement is made by officers or
employees of the corporation in the ordinary performance of their duties and
without the actual participation of such director) shall not be deemed
interested in such contract or other transaction under any of the provisions of
this Article, nor shall any such contract or transaction be void or voidable,
nor shall any such director be liable to account because of such interest nor
need any such interest be disclosed.

         Apart from and in addition to the other provisions of this Article, no
contract or other transaction between the corporation and any other corporation
or firm which provides for the purchase or sale of securities by such other
corporation or firms upon terms not less favorable to the corporation than
offered by such other corporation or firm to others, shall in any case be void
or voidable because of the fact that directors of the corporation are directors
of such other corporation or partners in such firm, nor shall any such director
be deemed interested in such contract or other transaction under any of the
provisions of this Article, nor shall any such director be liable to account in
respect thereof.

         No contract or other transaction between the corporation and any other
corporation, at least a majority of the stock of which having voting powers
owned or controlled by the corporation or which owns or controls at least a
majority of the stock having voting power of the corporation, shall in any case
be void or voidable because of the fact that directors of the corporation are
directors of such other corporation, nor shall any such director be deemed
interested in such contract or other transaction under any of the provisions of
this Article, nor shall any such director be liable to account because of such
interest nor need any such interest be disclosed.

         Any contract or act that shall be approved or ratified by the vote of
the holders of a majority of the capital stock of the corporation having voting
power which is represented in person or by proxy at any annual meeting of
stockholders or at any special meeting called for the purpose, among others, of
considering the approval or ratification of the acts of officers and/or
directors (provided that a lawful quorum of stockholders be there represented in
person or by proxy) shall be as valid and as binding upon the corporation and
upon all its stockholders as though it had been approved or ratified by every
stockholder of the corporation.

         ELEVENTH. A director of the corporation shall not be personally liable
to the corporation or its stockholders for monetary damages for breach of
fiduciary duty as a director except for liability (i) For any 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) Under section 174 of the Delaware General
Corporation Law, or (iv) for any transaction from which the director derived an
improper personal benefit.

         TWELFTH. Whenever a compromise or arrangement is proposed between this
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof, or on the
application of any receiver or receivers appointed for this corporation under
the provisions of Section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this corporation under the provisions of Section 279 of Title 8 of the
Delaware Code order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this corporation, as the case may
be, to be summoned in such manner as the said court directs. If a majority in
number representing three-fourth in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this corporation as consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all the creditors or class of creditors, and/or on all the
stockholders or class of stockholders, of this corporation, as the case may be,
and also on this corporation.


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         THIRTEENTH. Meetings of stockholders may be held outside the State of
Delaware, if the by-laws so provide. The books of the corporation may be kept
(subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designated from time to time by the
board of directors or in the by-laws of the corporation. Elections of directors
need not be by ballot unless the by-laws of the corporation shall so provide.

         FOURTEENTH. The corporation reserves the right to amend, alter, change
or repeal any provision contained in this certificate of incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.

         FIFTEENTH. Directors shall be divided into three classes, each class to
be as nearly equal in number as possible, the number assigned to each class to
be determined by the directors prior to the election of a particular class. In
the event that at any time or from time to time the number of directors is
increased, the newly created directorships resulting therefrom shall be filled
by a majority of the directors in office immediately prior to such increase.
Vacancies in any class of directors shall be filled by the majority of the
remaining directors in office. At the 1979 Annual Meeting of Stockholders, one
class shall be elected to a term of three years, another class to a term of two
years, and a third class to a term of one year; and at each subsequent annual
meeting, the successors to directors whose term shall expire that year shall be
elected to a term of three years.

         SIXTEENTH. Except as set forth below, the affirmative vote of the
holders of not less than 80% of the outstanding shares of the corporation
entitled to vote at an election of directors shall be required to authorize any
of the following items of business:

         (a) any merger or consolidation of the corporation into or with any
     other corporation;

         (b) any sale, lease, exchange, or other disposition of all or
     substantially all of the assets of the corporation to any other
     corporation, person or entity;

         (c) any purchase, lease or other acquisition by the corporation or any
     of its subsidiaries of any assets or securities of any other corporation,
     person or entity in exchange for securities of the corporation or any of
     its subsidiaries; or

         (d) any amendment of the Certificate of Incorporation which changes the
     percentage of votes of stockholders required for the transaction of any
     business or of any specified item of business, including, without
     limitation, amendments to the Certificate of Incorporation, unless such
     item of business has been by a majority of the entire Board of Directors of
     the corporation, in which event the approval of the holders of a majority
     of the outstanding share of the corporation entitled to vote at an election
     of directors shall be required to authorize any of the transactions set
     forth in clauses (a), (b), or (d) hereof and no such approval of
     stockholders shall be required to authorize any of the transactions set
     forth in clause (c) hereof.

         SEVENTEENTH. The following provision is inserted for the regulation and
conduct of the affairs of the corporation and it is intended that it be in
furtherance of and not in limitation or exclusion of the powers conferred by
law:

         The stockholders of the corporation shall have the authority to make,
alter, amend or repeal the by-laws of the corporation only upon the affirmative
vote of the holders of not less than 80% of the outstanding shares of the
corporation entitled to vote.

         WE,THE UNDERSIGNED, being each of the incorporators hereinbefore named,
for the purpose of forming a corporation pursuant to the General Corporation Law
of the State of Delaware, do make this certificate, hereby declaring and
certifying that the facts herein stated are true, and accordingly have hereunto
set our hands and seals this 30th day of March A. D. 1966.

         Signature

      /S/ S. A. LIVESAY
-----------------------------
          S. A. Livesay

      /S/ F. J. OBARA, JR
-----------------------------
          F. J. Obara, Jr

      /S/ A. D. GRIER
-----------------------------
          A. D. Grier


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STATE OF DELAWARE          )
                           )       ss:
COUNTY OF NEW CASTLE       )

         BE IT REMEMBERED that on this 30th day of March, A. D. 1966, personally
came before me, a Notary Public for the State of Delaware, S. H. Livesay, F. J.
Obara, Jr. and A. D. Grier, all of the parties to the foregoing certificate of
incorporation, known to me personally to be such, and severally acknowledged the
said certificate to be the act and deed of the signers respectively and that the
facts therein stated are truly set forth.

         GIVEN under my hand and seal of office the day and year aforesaid.

          Signature
          ---------

            /S/
-----------------------------
        Notary Public