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                                                                   Exhibit 3.1

                           FOURTH AMENDED AND RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                           STRATEGIC DIAGNOSTICS INC.


                                   ARTICLE I
                                      NAME

         The name of the Corporation is Strategic Diagnostics Inc.

                                   ARTICLE II
                                REGISTERED OFFICE

         The address of the registered office of the Corporation in the State of
Delaware is Corporation Trust Center, 1209 Orange Street, in the City of
Wilmington, County of New Castle. The name of the registered agent of the
Corporation at such address is The Corporation Trust Company. .

                                  ARTICLE III
                                    PURPOSES

         The nature of the business or purposes to be conducted or promoted by
the Corporation is to engage in any lawful act or activity for which
corporations may be organized under the General Corporation Law of Delaware.

                                   ARTICLE IV
                                  CAPITAL STOCK

         The total number of shares of all classes of capital stock which the
Corporation shall have the authority to issue is 54,664,362 shares, divided into
classes as follows:

                  2,164,362 shares shall be shares of Series A Convertible
                  Preferred Stock, with a par value of $.01 per share (the
                  "Series A Convertible Preferred Stock");

                  17,500,000 shares shall be shares of Preferred Stock, with a
                  par value of $.01 per share (the "Blank Check Preferred
                  Stock"); and

                  35,000,000 shares shall be shares of Common Stock, with a par
                  value of $.01 per share (the "Common Stock");
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The following is a statement of the powers, preferences, rights, qualifications,
limitations and restrictions of the Series A Convertible Preferred Stock, the
Blank Check Preferred Stock and the Common Stock:

         PART A - Series A Convertible Preferred Stock

              1.   Number of Shares. The series of Preferred Stock designated
and known as "Series A Convertible Preferred Stock" shall consist of 2,164,362
shares.

              2.   Voting. Except as otherwise may be provided in these terms of
the Series A Convertible Preferred Stock or by law, the Series A Convertible
Preferred Stock and all other classes and series of stock of the Corporation
otherwise entitled to vote shall vote together as a single class on all actions
to be taken by the stockholders of the Corporation. Each share of Series A
Convertible Preferred Stock shall entitle the holder thereof to such number of
votes per share on each such action as shall equal the nearest whole number of
shares of Common Stock into which each share of Series A Convertible Preferred
Stock is then convertible.

              3.   Dividends. The holders of the Series A Convertible Preferred
Stock shall be entitled to receive, out of funds legally available therefor,
when and if declared by the Board of Directors, any dividend on or with respect
to Common Stock (other than a dividend payable solely in shares of Common Stock)
in an amount equal to the product obtained by multiplying the dividend declared
or payable on each share of Common Stock times the nearest whole number of
shares of Common Stock into which each share of Series A Convertible Preferred
Stock is then convertible.

              4.   Liquidation. Upon any liquidation, dissolution or winding up
of the Corporation (other than in connection with a reorganization of the
Corporation in which the rights and preferences of the Series A Convertible
Preferred Stock are not adversely affected), whether voluntary or involuntary,
the holders of Series A Convertible Preferred Stock shall be entitled, before
any distribution or payment is made upon any stock ranking on liquidation junior
to the Series A Convertible Preferred Stock, to be paid an amount equal to
$2.9466849 per share of Series A Convertible Preferred Stock up to an aggregate
maximum of $6,377,693 (in the aggregate, the "Liquidation Preference") (such
amount payable with respect to one share of Series A Convertible Preferred Stock
sometimes shall be referred to as the "Liquidation Payment"); provided, however,
that the Liquidation Preference shall be automatically reduced in an aggregate
amount equal to any dividends paid to the holders of Series A Convertible
Preferred Stock and the Liquidation Payment shall be reduced on a per share
basis for such payment of dividends. If upon such liquidation, dissolution or
winding up of the Corporation, whether voluntary or involuntary, the assets to
be distributed among the holders of Series A Convertible Preferred Stock shall
be insufficient to permit payment to the holders of the Series A Convertible
Preferred Stock of the full Liquidation Preference, then the entire assets of
the Corporation legally available for distribution shall be distributed ratably
among the holders of Series A Convertible Preferred Stock. Upon any such
liquidation, dissolution or winding up of the Corporation, after the holders of
Series A Convertible Preferred Stock shall have been paid the full Liquidation
Preference, the remaining net assets of the Corporation may be distributed to
the holders of stock ranking on liquidation junior to the Series A Convertible
Preferred Stock. Written notice of such liquidation, dissolution or winding up,
stating a payment date, the amount of the Liquidation Payment and the place
where said Liquidation Payment shall be payable, shall be given by mail, postage
prepaid, or by telex to non-U.S. residents, not less than 20 days prior to the
payment date stated therein, to the holders of record of Series A Convertible
Preferred Stock, such notice to be addressed to each such holder at its address
as shown by the records of the Corporation.
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              5.   Restrictions. At any time when shares of Series A Convertible
Preferred Stock are outstanding, except where the vote or written consent of the
holders of a greater number of shares of the Corporation is required by law or
by the Certificate of Incorporation, and in addition to any other vote required
by law or the Certificate of Incorporation, without the approval of the holders
of at least two-thirds of the then outstanding shares of Series A Convertible
Preferred Stock, given in writing or by vote at a meeting, consenting or voting
(as the case may be) separately as a series, the Corporation will not:

                  5A. Create or authorize the creation of any additional class
or series of shares of stock unless the same ranks junior to the Series A
Convertible Preferred Stock as to the distribution of assets on the liquidation,
dissolution or winding up of the Corporation, or increase the authorized amount
of the Series A Convertible Preferred Stock or increase the authorized amount of
any additional class or series of shares of stock unless the same ranks junior
to the Series A Convertible Preferred Stock as to the distribution of assets on
the liquidation, dissolution or winding up of the Corporation, or create or
authorize any obligation or security convertible into shares of Series A
Convertible Preferred Stock or into shares of any other class or series of stock
unless the same ranks junior to the Series A Convertible Preferred Stock as to
the distribution of assets on the liquidation, dissolution or winding up of the
Corporation; or

                  5B. Redeem or otherwise acquire any shares of Series A
Convertible Preferred Stock, except as expressly authorized in paragraph 7
hereof or pursuant to a purchase offer made pro rata to all holders of the
shares of Series A Convertible Preferred Stock on the basis of the aggregate
number of outstanding shares of Series A Convertible Preferred Stock then held
by each such holder.

              6.   Conversions. The holders of shares of Series A Convertible
Preferred Stock shall have the following conversion rights:

                  6A. Right to Convert. Subject to the terms and conditions of
this paragraph 6, the holder of any share or shares of Series A Convertible
Preferred Stock shall have the right, at its option at any time, to convert any
such shares of Series A Convertible Preferred Stock (except that upon any
liquidation of the Corporation the right of conversion shall terminate at the
close of business on the business day fixed for payment of the Liquidation
Payment) into an equal number of fully paid and nonassessable shares of Common
Stock, subject to adjustment as provided in subparagraphs 6D and 6E. Such rights
of conversion shall be exercised by the holder thereof by giving written notice
that the holder elects to convert a stated number of shares of Series A
Convertible Preferred Stock into Common Stock and by surrender of a certificate
or certificates for the shares so to be converted to the Corporation at its
principal office (or such other office or agency of the Corporation as the
Corporation may designate by notice in writing to the holders of the Series A
Convertible Preferred Stock) at any time during its usual business hours on the
date set forth in such notice, together with a statement of the name or names
(with address) in which the certificate or certificates for shares of Common
Stock shall be issued.
<PAGE>

                  6B. Issuance of Certificates; Time Conversion Effected.
Promptly after the receipt of the written notice referred to in subparagraph 6A
and surrender of the certificate or certificates for the share or shares of
Series A Convertible Preferred Stock to be converted, the Corporation shall
issue and deliver, or cause to be issued and delivered, to the holder,
registered in such name or names as such holder may direct, a certificate or
certificates for the number of whole shares of Common Stock issuable upon the
conversion of such share or shares of Series A Convertible Preferred Stock. To
the extent permitted by law, such conversion shall be deemed to have been
effected as of the close of business on the date on which such written notice
shall have been received by the Corporation and the certificate or certificates
for such share or shares shall have been surrendered as aforesaid, and at such
time the rights of the holder of such share or shares of Series A Convertible
Preferred Stock shall cease, and the person or persons in whose name or names
any certificate or certificates for shares of Common Stock shall be issuable
upon such conversion shall be deemed to have become the holder or holders of
record of the shares represented thereby.

                  6C. Fractional Shares; Dividends; Partial Conversion. No
fractional shares shall be issued upon conversion of Series A Convertible
Preferred Stock into Common Stock and no payment or adjustment shall be made
upon any conversion on account of any cash dividends on the Common Stock issued
upon such conversion. At the time of each conversion, the Corporation shall pay
in cash an amount equal to all dividends accrued and unpaid on the shares of
Series A Convertible Preferred Stock surrendered for conversion to the date upon
which such conversion is deemed to take place as provided in subparagraph 6B. In
case the number of shares of Series A Convertible Preferred Stock represented by
the certificate or certificates surrendered pursuant to subparagraph 6A exceeds
the number of shares converted, the Corporation shall, upon such conversion,
execute and deliver to the holder, at the expense of the Corporation, a new
certificate or certificates for the number of shares of Series A Convertible
Preferred Stock represented by the certificate or certificates surrendered which
are not to be converted. If any fractional share of Common Stock would, except
for the provisions of the first sentence of this subparagraph 6C, be delivered
upon such conversion, the Corporation, in lieu of delivering such fractional
share, shall pay to the holder surrendering the Series A Convertible Preferred
Stock for conversion an amount in cash equal to the current market price of such
fractional share as determined in good faith by the Board of Directors of the
Corporation.

                  6D. Subdivision or Combination of Common Stock. In case the
Corporation shall at any time subdivide (by any stock split, stock dividend or
otherwise) its outstanding shares of Common Stock into a greater number of
shares, the number of shares of Common Stock issuable upon conversion of each
share of Series A Convertible Preferred Stock shall be increased in proportion
to such increase in outstanding shares, and, conversely, in case the outstanding
shares of Common Stock shall be combined into a smaller number of shares, the
number of shares of Common Stock issuable upon conversion of each share of
Series A Convertible Preferred Stock shall be decreased in proportion to such
decrease in outstanding shares.
<PAGE>

                  6E. Reorganization or Reclassification. If any capital
reorganization or reclassification of the capital stock of the Corporation shall
be effected in such a way that holders of Common Stock shall be entitled to
receive stock, securities or assets with respect to or in exchange for Common
Stock, then, as a condition of such reorganization or reclassification, lawful
and adequate provisions shall be made whereby each holder of a share or shares
of Series A Convertible Preferred Stock shall thereupon have the right to
receive, upon the basis and upon the terms and conditions specified herein and
in lieu of the shares of Common Stock immediately theretofore receivable upon
the conversion of such share or shares of Series A Convertible Preferred Stock,
such shares of stock, securities or assets as may be issued or payable with
respect to or in exchange for a number of outstanding shares of such Common
Stock equal to the number of shares of such Common Stock immediately theretofore
receivable upon such conversion had such reorganization or reclassification not
taken place, and in any such case appropriate provisions shall be made with
respect to the rights and interests of such holder to the end that the
provisions hereof shall thereafter be applicable, as nearly as may be, in
relation to any shares of stock, securities or assets thereafter deliverable
upon the exercise of such conversion rights.

                  6F. Certain Notices. In case at any time:

                           (1) the Corporation shall declare any dividend upon
its Common Stock payable in cash or stock or make any other distribution to the
holders of its Common Stock;

                           (2) the Corporation shall offer for subscription pro
rata to the holders of its Common Stock any additional shares of stock of any
class or other rights;

                           (3) there shall be any capital reorganization or
reclassification of the capital stock of the Corporation, or a consolidation or
merger of the Corporation with or into, or a sale of all or substantially all
its assets to, another entity or entities; or

                           (4) there shall be a voluntary or involuntary
dissolution, liquidation or winding up of the Corporation;

then, in any one or more of said cases, the Corporation shall give, by first
class mail, postage prepaid, or by telex to non U.S. residents, addressed to
each holder of any shares of Series A Convertible Preferred Stock at the address
of such holder as shown on the books of the corporation, (a) at least 20 days'
prior written notice of the date on which the books of the Corporation shall
close or a record shall be taken for such dividend, distribution or subscription
rights or for determining rights to vote in respect of any such reorganization,
reclassification, consolidation, merger, sale, dissolution, liquidation or
winding up and (b) in the case of any such reorganization, reclassification,
consolidation, merger, sale, dissolution, liquidation or winding up, at least 20
days' prior written notice of the date when the same shall take place. Such
notice in accordance with the foregoing clause (a) shall also specify, in the
case of any such dividend, distribution or subscription rights, the date on
which the holders of Common Stock shall be entitled thereto and such notice in
accordance with the foregoing clause (b) shall also specify the date on which
the holders of Common Stock shall be entitled to exchange their Common Stock for
securities or other property deliverable upon such reorganization,
reclassification, consolidation, merger, sale, dissolution, liquidation or
winding up, as the case may be.
<PAGE>

                  6G. Stock to be Reserved. The Corporation will at all times
reserve and keep available out of its authorized Common Stock, solely for the
purpose of issuance upon the conversion of Series A Convertible Preferred Stock
as herein provided, such number of shares of Common Stock as shall then be
issuable upon the conversion of all outstanding shares of Series A Convertible
Preferred Stock. The Corporation covenants that, assuming the receipt by the
Corporation of the consideration therefor, all shares of Common Stock which
shall be so issued shall be duly and validly issued and fully paid and
nonassessable.

                  6H. No Reissuance of Series A Convertible Preferred Stock.
Shares of Series A Convertible Preferred Stock which are converted into shares
of Common Stock as provided herein shall be canceled and shall not be reissued.

                  6I. Closing of Books. The Corporation will at no time close
its transfer books against the transfer of any Series A Convertible Preferred
Stock or of any shares of Common Stock issued or issuable upon the conversion of
any shares of Series A Convertible Preferred Stock in any manner which
interferes with the timely conversion of such Series A Convertible Preferred
Stock, except as may otherwise be required to comply with applicable securities
laws.

                  6J. Mandatory Conversion. If the closing share price of Common
Stock listed on the NASDAQ National Market System equals or exceeds $4.50 per
share for a period of forty-five (45) consecutive business days, all outstanding
shares of Series A Convertible Preferred Stock shall automatically convert to
shares of Common Stock.

              7.   Redemption. The shares of Series A Convertible Preferred
Stock shall be redeemed as follows:

                  7A. Redemption at Holders' Option. In the event the
Corporation enters into a merger, consolidation, recapitalization,
reorganization or any other transaction pursuant to which the Series A
Convertible Preferred Stock would be converted into or exchanged for: (i)
preferred stock with lesser rights or a lesser Liquidation Preference; or (ii)
for common stock that in the aggregate has a lesser aggregate fair market value
than the Liquidation Preference; or (iii) for an aggregate amount of cash that
is less than the Liquidation Preference; then on the written request (the
"Holder Redemption Request") of the holders of at least 66 2/3% of the
outstanding shares of Series A Convertible Preferred Stock, then at or before
the closing of such transaction, the Corporation shall redeem from each holder
of shares of Series A Convertible Preferred Stock all of the shares of Series A
Convertible Preferred Stock held by such holder for an aggregate amount equal to
the Liquidation Preference.

                  7B. Redemption at Corporation's Option. Upon at least sixty
(60) days' prior written notice, the Corporation may redeem effective at any
time on or after June 23, 2001, from each holder of shares of Series A
Convertible Preferred Stock all of the shares of Series A Convertible Preferred
Stock held by such holder.
<PAGE>

                  7C. Redemption Price and Payment. The Series A Convertible
Preferred Stock to be redeemed pursuant to Subparagraph 7B shall be redeemed by
paying for each share in cash an amount equal to the Liquidation Payment, such
amount also being referred to as the "Redemption Price". Such payment shall be
made in full to the holders entitled thereto.

                  7D. Redemption Mechanics. At least 20 but not more than 30
days prior to the date of any redemption (the "Redemption Date"), written notice
(the "Redemption Notice") shall be given by the Corporation by mail, postage
prepaid, or by telex to non-U.S. residents for which telex instructions shall
have been provided to the Corporation for such purpose, to each holder of record
(at the close of business on the business day next preceding the day on which
the Redemption Notice is given) of shares of Series A Convertible Preferred
Stock notifying such holder of the redemption and specifying the Redemption
Price, the Redemption Date and the place where said Redemption Price shall be
payable. The holders of at least 66-2/3% of the Series A Convertible Preferred
Stock may rescind any Holder Redemption Request at any time prior to the close
of business on the 10th day after receipt of the Redemption Notice by giving
written notice of rescission to the Corporation; provided, that the holders of
Series A Convertible Preferred Stock may not thereafter submit a subsequent
Holder Redemption Request in respect of the same transaction. The Redemption
Notice shall be addressed to each holder at his address as shown by the records
of the Corporation. From and after the close of business on the Redemption Date,
unless there shall have been a default in the payment of the Redemption Price,
all rights of holders of shares of Series A Convertible Preferred Stock (except
the right to receive the Redemption Price) shall cease with respect to such
shares, and such shares shall not thereafter be transferred on the books of the
Corporation or be deemed to be outstanding for any purpose whatsoever. If the
funds of the Corporation legally available for redemption of shares of Series A
Convertible Preferred Stock on the Redemption Date are insufficient to redeem
the total number of outstanding shares of Series A Convertible Preferred Stock,
the holders of shares of Series A Convertible Preferred Stock shall share
ratably in any funds legally available for redemption of such shares according
to the respective amounts which would be payable with respect to the full number
of shares owned by them if all such outstanding shares were redeemed in full.
The shares of Series A Convertible Preferred Stock not redeemed shall remain
outstanding and entitled to all rights and preferences provided herein. At any
time thereafter when additional funds of the Corporation are legally available
for the redemption of such shares of Series A Convertible Preferred Stock, such
funds will be used, at the end of the next succeeding fiscal quarter, to redeem
the balance of such shares, or such portion thereof for which funds are then
legally available, on the basis set forth above.

                  7E. Redeemed or Otherwise Acquired Shares to be Retired. Any
shares of Series A Convertible Preferred Stock redeemed pursuant to this
paragraph 7 or otherwise acquired by the Corporation in any manner whatsoever
shall be canceled and shall not under any circumstances be reissued; and the
Corporation may from time to time take such appropriate corporate action as may
be necessary to reduce accordingly the number of authorized shares of Series A
Convertible Preferred Stock.
<PAGE>

         PART B - Blank Check Preferred Stock

              1.   Designation and Amount. The designation of this class of
capital stock shall be "Blank Check Preferred Stock," par value $.01 per share.
Subject to the provisions of this Article IV and the express provisions of each
series of Blank Check Preferred Stock, the Board of Directors is hereby
empowered to cause the Corporation to issue from time to time, in one or more
series, up to 17,500,000 shares of Blank Check Preferred Stock.

              2.   Rights. The powers, designations, preferences, terms,
conditions, privileges and other rights of each series of Blank Check Preferred
Stock shall be determined by the Board of Directors in accordance with Section
151 of the Delaware General Corporation Law, subject to the provisions of Part
A, Paragraph 5A of this Article IV. Except in respect of the particulars fixed
by the Board of Directors for each such series, all Blank Check Preferred Stock
shall be of equal rank and identical.

         PART C - Common Stock

              1.   Designation and Amount. The designation of this class of
capital stock shall be "Common Stock," par value $.01 per share ("Common
Stock"). The number of authorized shares of Common Stock may be increased or
decreased (but not below the number of shares thereof then outstanding) by the
affirmative vote of the holders of the majority of the stock of the Corporation
entitled to vote, irrespective of the provisions of Section 242(b)(2) of the
Delaware General Corporation Law.

              2.   Voting. Each share of Common Stock shall have one vote upon
all matters to be voted on by the holders of Common Stock, which voting rights
shall not be cumulative.

              3.   Other Rights. Each share of Common Stock shall be entitled to
participate equally in all dividends payable with respect to the Common Stock
and to share ratably, subject to the rights and preferences of the Series A
Convertible Preferred Stock and/or any series of the Blank Check Preferred
Stock, in all assets of the Corporation in the event of any voluntary or
involuntary liquidation, dissolution or winding up of the affairs of the
Corporation, or upon any distribution of the assets of the Corporation.

                                   ARTICLE V
                          CERTAIN BUSINESS COMBINATIONS

         PART A - Vote Required for Certain Business Combinations.

              1.   Required Vote for Certain Business Combinations. In addition
to any affirmative vote required by law or by this Certificate of Incorporation,
and except as otherwise expressly provided in Paragraph 2 of this Article V,
Part A:

                   1A.  any merger or consolidation of the Corporation or any
Subsidiary (as hereinafter defined) with (a) any Interested Stockholder (as
hereinafter defined) or (b) any other corporation or entity (whether or not
itself an Interested Stockholder) which is, or after such merger or
consolidation would be, an Affiliate (as hereinafter defined) of any Interested
Stockholder; or

                   1B.  any sale, lease, exchange, mortgage, pledge, transfer or
other disposition (in one transaction or a series of transactions) to or with
any Interested Stockholder or any Affiliate of any Interested Stockholder of any
assets of the Corporation or any Subsidiary having an aggregate Fair Market
Value (as hereinafter defined) of $5,000,000 or more; or
<PAGE>

                   1C.  the issuance or transfer by the Corporation or any
Subsidiary (in one transaction or a series of transactions) of any securities of
the Corporation or any Subsidiary to any Interested Stockholder or any Affiliate
of any Interested Stockholder in exchange for cash, securities or other property
(or a combination thereof) having an aggregate Fair Market Value of $5,000,000
or more; or

                   1D.  the adoption of any plan or proposal for the
liquidation, dissolution or winding up of the Corporation proposed by or on
behalf of any Interested Stockholder or any Affiliate of any Interested
Stockholder; or

                   1E.  any reclassification of securities (including any
reverse stock split), or recapitalization of the Corporation, or any merger or
consolidation of the Corporation with any of its Subsidiaries or any other
transaction (whether or not with or into or otherwise involving any Interested
Stockholder) which has the effect, directly or indirectly, of increasing the
proportionate share of the outstanding shares of any class of equity or
convertible securities of the Corporation or any Subsidiary which is directly or
indirectly owned by any Interested Stockholder or any Affiliate of any
Interested Stockholder;

shall require, subject to Paragraph 2 of this Article V, Part A, the affirmative
vote of the holders of at least two-thirds of the voting power of the then
outstanding Voting Stock (as hereinafter defined), voting together as a single
class at a duly constituted meeting of stockholders called expressly for such
purpose. Such affirmative vote shall be required notwithstanding the fact that
no vote may be required, or that a lesser percentage may be specified, by law.

              2.   Definition of "Business Combination. The term "Business
Combination" as used in this Article V shall mean any transaction which is
referred to in any one or more of Subparagraphs (1A) through (1E) of this
Paragraph 1 of Article V, Part A.

         PART B - When Higher Vote is Not Required.

         The provisions of Paragraph 1 of this Article V, Part A, shall not be
applicable to any particular Business Combination, and such Business Combination
shall require only such affirmative vote, if any, as is required by law and any
other provision of this Certificate of Incorporation, if all of the conditions
specified in either of the following Paragraph 1 or 2 or this Part B are met:

              1.   Approval by Continuing Directors. The Business Combination
shall have been approved by the affirmative vote of a majority of the Continuing
Directors (as herein defined) then in office.

              2.   Price and Procedure Requirements. All of the following
conditions shall have been met:

                   2A.  The aggregate amount of the cash and the Fair Market
Value, as of the date of the consummation of the Business Combination, of
consideration other than cash to be received per share by holders of common
stock in such Business Combination shall be at least equal to the highest of the
following:
<PAGE>

                        (1)  (if applicable) the highest per share price
(including any brokerage commissions, transfer taxes and soliciting dealers'
fees) paid by the Interested Stockholder for any shares of common stock acquired
by it (1) within the two-year period immediately prior to and including the
first public announcement of the proposal of the Business Combination (the
"Announcement Date") or (2) in the transaction in which it became an Interested
Stockholder, whichever is higher; and

                        (2)  the Fair Market Value per share of common stock on
the Announcement Date or on the date on which the Interested Stockholder became
an Interested Stockholder (such latter date is referred to in this Article V as
the "Determination Date"), whichever is higher.

                   2B.  The aggregate amount of the cash and the Fair Market
Value, as of the date of the date of the consummation of the Business
Combination, of consideration other than cash to be received per share by
holders of shares of any other class of outstanding Voting Stock in such
Business Combination shall be at least equal to the highest of the following (it
being intended that the requirements of this Subparagraph 2B shall be required
to be met with respect to every other class of outstanding Voting Stock, whether
or not the Interested Stockholder has previously acquired any shares of a
particular class of Voting Stock):

                        (1)  (if applicable) the highest per share price
(including any brokerage commissions, transfer taxes and soliciting dealers'
fees) paid by the Interested Stockholder for any shares of such class of Voting
Stock acquired by it (1) within the two-year period immediately prior to and
including the Announcement Date or (2) in the transaction in which it became an
Interested Stockholder, whichever is higher;

                        (2)  (if applicable) the highest preferential amount per
share which the holders of shares of such class of Voting Stock are entitled to
receive from the Corporation in the event of any voluntary or involuntary
liquidation, dissolution or winding up of the Corporation; and

                        (3)  the Fair Market Value per share of such class of
voting Stock on the Announcement Date or on the Determination Date, whichever is
higher.

                   2C.  The consideration to be received by holders of a
particular class of outstanding Voting Stock shall be in cash or in the same
form as the Interested Stockholder has previously paid for shares of such class
of Voting Stock. If the Interested Stockholder has paid for shares of any class
of Voting Stock with varying forms of consideration, the form of consideration
for such class of Voting Stock shall be either cash or the form used to acquire
the largest number of shares of such class of Voting Stock previously acquired
by such Interested Stockholder.
<PAGE>

                   2D.  After such Interested Stockholder has become an
Interested Stockholder and prior to the consummation of such Business
Combination: (a) there shall have been (1) no failure to declare and pay at
regular dates therefor the full amount of any dividends (whether or not
cumulative) payable on any class or series of preferred stock, except as
approved by the affirmative vote of a majority of the Continuing Directors; (2)
no reduction in the annual rate of dividends paid on the common stock (except as
necessary to reflect any subdivision of the common stock), except as approved by
the affirmative vote of a majority of the Continuing Directors; and (3) an
increase in such annual rate of dividends as necessary to reflect any
reclassification (including any reverse stock split), recapitalization,
reorganization or any similar transaction which has the effect of reducing the
number of outstanding shares of the common stock, unless the failure so to
increase such annual rate is approved by the affirmative vote of a majority of
the Continuing Directors; and (b) such Interested Stockholder shall not have
become the beneficial owner of any additional shares of Voting Stock except as
part of the transaction which results in such Interested Stockholder becoming an
Interested Stockholder.

                   2E.  After such Interested Stockholder has become an
Interested Stockholder, such Interested Stockholder shall not have received the
benefit, directly or indirectly (except proportionately as a stockholder), of
any loans, advances, guarantees, pledges or other financial assistance or any
tax credits or other tax advantages provided by the Corporation, whether in
anticipation of or in connection with such Business Combination or otherwise,
unless such transaction shall have been approved or ratified by the affirmative
vote of a majority of the Continuing Directors after such person shall have
become an Interested Stockholder.

                   2F.  A proxy or information statement describing the proposed
Business Combination and complying with the requirements of the Securities
Exchange Act of 1934 and the rules and regulations thereunder (or any subsequent
provisions replacing such Act, rules and regulations) shall be mailed to public
stockholders of the Corporation at least 20 days prior to the consummation of
such Business Combination (whether or not such proxy or information statement is
required to be mailed pursuant to such Act, rules or regulations or subsequent
provisions thereof).

         PART C - Certain Definitions.

         For the purposes of this Article V:

              1.   A "person" shall mean an individual, a Group Acting in
Concert, a corporation, a partnership, an association, a joint stock company, a
trust, a business trust, a government or political subdivision, any
unincorporated organization, or any other association or entity.

              2.   "Interested Stockholder" shall mean any person who or which:

                   2A.  is the beneficial owner, directly or indirectly, of 15%
or more of the voting power of the then outstanding shares of Voting Stock; or

                   2B.  is an Affiliate of the Corporation and at any time
within the two-year period immediately prior to and including the date in
question was the beneficial owner, directly or indirectly, of 15% or more of the
voting power of the then outstanding shares of Voting Stock; or
<PAGE>

                   2C.  is an assignee of or has otherwise succeeded to the
beneficial ownership of any shares of Voting Stock which were at any time within
the two-year period immediately prior to and including the date in question
beneficially owned by any Interested Stockholder, if such assignment or
succession shall have occurred in the course of a transaction or series of
transactions not involving a public offering within the meaning of the
Securities Act of 1933 (or any subsequent provisions replacing such Act or the
rules and regulations promulgated thereunder) and such assignment or succession
was not approved by a majority of the Continuing Directors;

provided, however, that the term "Interested Stockholder" shall not include (a)
the Corporation; (b) any Subsidiary of the Corporation; (c) any person, directly
or indirectly, owning of record or beneficially 100% of the issued and
outstanding capital stock of the Corporation (other than directors' qualifying
shares, if any); (d) any employee benefit plan or compensation arrangement of
the Corporation or any Subsidiary of the Corporation; (e) any person holding
shares of voting Stock organized, appointed or established by the Corporation or
any Subsidiary for or pursuant to the terms of any such employee benefit plan or
compensation arrangement; or (f) any Grandfathered Person unless such
Grandfathered Person becomes, after the closing of the initial public offering
of shares of common stock of the Corporation, the beneficial owner of more than
the Grandfathered Percentage of the Voting Stock then outstanding. Any
Grandfathered Person who becomes, after the close of business on the date of the
closing of the initial public offering of shares of common stock of the
Corporation, the beneficial owner of less than 15% of the voting power of the
then outstanding shares of Voting Stock shall cease to be a Grandfathered
Person.

Notwithstanding the foregoing, no person shall become an "Interested
Stockholder" as the result of an acquisition of Voting Stock by the Corporation
which, by reducing the number of shares outstanding, increases the proportionate
number of shares beneficially owned by such person to 15% (or, if applicable,
the Grandfathered Percentage with respect to such person) or more of the voting
power of the then outstanding shares of Voting Stock; provided, however, that if
a person shall become the beneficial owner of 15% (or, if applicable, the
Grandfathered Percentage with respect to such person) or more of the voting
power of the then outstanding shares of Voting Stock by reason of share
purchases by the Corporation and shall, after such share purchases by the
Corporation, become the beneficial owner of any additional shares of Voting
Stock of the Corporation (other than any shares of Voting Stock issued to such
person as a result of a stock dividend, stock split, reclassification,
recapitalization, or other similar transaction involving the issuance of shares
of Voting Stock on a pro rata basis to all holders of voting Stock), then such
person shall be deemed to be an "Interested Stockholder" if immediately
thereafter the voting power of the shares of Voting Stock beneficially owned by
such person equals or exceeds 15% (or in the case of a Grandfathered Person, the
Grandfathered Percentage with respect to such person) or more of the voting
power of all of the shares of Voting Stock then outstanding.

              3.   A person shall be deemed the "beneficial owner" of, and shall
be deemed to beneficially own, any Voting Stock:

                   3A.  which such person or any of such person's Affiliates or
Associates, directly or indirectly, beneficially owns (as determined pursuant to
Rule 13d-3 of the Rules and Regulations promulgated by the Securities and
Exchange Commission under the Securities Exchange Act of 1934, as amended (the
"1934 Act")); or
<PAGE>

                   3B.  which such person or any of its Affiliates or
Associates, directly or indirectly, has or shares with respect to the Voting
Stock (a) the right to acquire, or direct the acquisition of (whether such right
is exercisable immediately, or only after the passage of time or upon the
satisfaction of any conditions, or both), such Voting Stock pursuant to any
agreement, arrangement, understanding or otherwise (whether or not in writing)
(other than customary arrangements with and between underwriters and selling
group members with respect to a bona fide public offering of securities) or upon
the exercise of conversion rights, exchange rights, warrants or options, or
otherwise; provided, however, that a person shall not be deemed the "beneficial
owner" of, or to "beneficially own," securities tendered pursuant to a tender or
exchange offer made by or on behalf of such person or any of such person's
Affiliates or Associates until such tendered securities are accepted for
purchase or exchange, (b) the right to vote, or to direct the voting of, such
Voting Stock pursuant to any agreement, arrangement, understanding or otherwise
(whether or not in writing) (provided that a person shall not be deemed to be
the beneficial owner of any securities if the agreement, arrangement or
understanding to vote such security arises solely from a revocable proxy given
in response to a public proxy or consent solicitation made pursuant to, and in
accordance with, the Rules and Regulations promulgated under the 1934 Act and is
not also then reportable by such person on Schedule 13D under the 1934 Act (or
any comparable or successor report)), or (c) the right to dispose of, or to
direct the disposition of, such Voting Stock pursuant to any agreement,
arrangement, understanding or otherwise (whether or not in writing) (other than
customary arrangement with and between underwriters and selling group members
with respect to a bona fide public offering of securities ); or

                   3C.  which is beneficially owned, directly or indirectly, by
any other person (or any Affiliate or Associate thereof) with which such person
or any of such person's Affiliates or Associates has any agreement, arrangement,
understanding or otherwise (whether or not in writing) (other than customary
arrangements with and between underwriters and selling group members with
respect to a bona fide public offering of securities) for the purpose of
acquiring, holding, voting (except pursuant to a revocable proxy described in
Subparagraph 3B above) or disposing of any shares of Voting Stock.

provided, however, that (1) no person engaged in business as an underwriter of
securities shall be deemed the beneficial owner of any securities acquired
through such person's participation as an underwriter in good faith in a firm
commitment underwriting until the expiration of 40 days after the date of such
acquisition and (2) no person who is a director or an officer of the Corporation
shall be deemed, solely as a result of his or her participation as director or
officer of the Corporation, the beneficial owner of any securities of the
Corporation that are beneficially owned by any other director or officer of the
Corporation.

                   3D.  Notwithstanding anything in the definition of beneficial
owner to the contrary, the phrase "then outstanding," when used with reference
to a person's beneficial ownership of securities of the Corporation, shall mean
the number of such securities then issued and outstanding together with the
number of such securities not then actually issued and outstanding which such
person would be deemed to own beneficially hereunder.
<PAGE>

                   3E.  "Affiliate" and "Associate" shall have the respective
meanings ascribed to such terms in Rule 12b-2 f the General Rules and
Regulations under the 1934 Act (or any subsequent provisions replacing the 1934
Act or the rules and regulations promulgated thereunder); provided, however,
that no person who is a director or officer of the Corporation shall be deemed
an Affiliate or Associate of any other director or officer of the Corporation
solely as a result of his or her position as a director or officer of the
Corporation.

                   3F.  "Subsidiary" means any corporation of which a majority
of any class of equity security is owned, directly or indirectly, by the
Corporation; provided, however, that for the purposes of the definition of
Interested Stockholder set forth in Paragraph 2 of this Part C, the term
"Subsidiary" shall mean only a corporation of which a majority of each class of
equity security is owned, directly or indirectly, by the Corporation.

                   3G.  "Continuing Director" means (i) any member of the Board
of Directors of the Corporation who is not an Interested Stockholder of an
Affiliate or Associate of an Interested Stockholder and was a member of the
Board of Directors prior to the time that the interested Stockholder became an
Interested Stockholder, and (ii) any person who subsequently becomes a member of
the Corporation's Board of Directors who is not an Associate or Affiliate of an
Interested Stockholder and is recommended or approved by the affirmative vote of
a majority of the Continuing Directors.

                   3H.  "Fair Market Value" means:

                        (1)  in the case of stock, the highest closing sale
price during the 30-day period immediately prior to and including the date in
question of a share of such stock on the principal United States securities
exchange registered under the 1934 Act (or any subsequent provisions replacing
such Act or rules or regulations promulgated thereunder) on which such stock is
listed, or, if such stock is not listed on any such exchange, the highest
closing bid quotation with respect to a share of such stock during the 30-day
period immediately prior to and including the date in question on the National
Association of Securities Dealers Automated Quotation System or any comparable
value system then in use, or if no such quotations are available, the fair
market value on the date in question of a share of such stock as determined by
the affirmative vote of a majority of the Continuing Directors of the Board of
Directors in good faith; and

                        (2)  in the case of property other than cash or stock,
the fair market value of such property on the date in question is determined by
an affirmative vote of a majority of the Continuing Directors of the Board of
Directors in good faith.

                   3I.  "Group Acting in Concert" shall mean persons seeking to
combine or pool their voting or other interests in the securities of the
Corporation for a common purpose, pursuant to any contract, understanding or
relationship, agreement or other arrangement, whether written, oral or
otherwise, or any "group of persons" as defined under Section 13(d) of the 1934
Act (or any subsequent provisions replacing such Act or rules or regulations
promulgated thereunder). When persons act together for any such purpose, their
group is deemed to have acquired their stock.
<PAGE>

                   3J.  In the event of any Business Combination in which the
Corporation survives, the phrase "consideration other than cash to be received"
as used in this Article V shall include the shares of common stock and/or the
shares of any other class of outstanding Voting Stock retained by the holders of
such shares.

                   3K.  "Voting Stock" shall mean the outstanding shares of
capital stock of the Corporation entitled, at the time, to vote generally in the
election of Directors.

                   3L.  "Grandfathered Percentage" shall mean , with respect to
any Grandfathered Person, the percentage of the voting power of the then
outstanding shares of Voting Stock that such Grandfathered Person beneficially
owns as of the close business on the date of the closing of the initial public
offering of shares of common stock of the Corporation in the fall of 1993 plus
an additional two (2) percentage points; provided, however, that in the event
the underwriters exercise their over-allotment option in connection with this
initial public offering of shares of common stock, the Grandfathered Percentage
shall, from and after the closing of such over-allotment option, mean, with
respect to any Grandfathered Person, the percentage of the voting power of the
then outstanding shares of Voting Stock that such Grandfathered Person
beneficially owns as of the close of business on the date of the closing of the
over-allotment option plus an additional two (2) percentage points; and
provided, further, that, in the event of any Grandfathered Person shall sell,
transfer or otherwise dispose of any outstanding shares of Voting Stock after
the close of business on the date of the closing of the initial public offering
of the Corporation's common stock in the fall of 1993, the Grandfathered
Percentage shall, subsequent to such sale, transfer or disposition, mean, with
respect to such Grandfathered Person, the lesser of (i) the Grandfathered
Percentage as in effect immediately prior to such sale, transfer, or disposition
or (ii) the percentage of the voting power of the then outstanding shares of
Voting Stock that such Grandfathered Person beneficially owns immediately
following such sale, transfer or disposition plus an additional two (2)
percentage points.

                   3M.  "Grandfathered Person" shall mean any Person who or
which, together with all Affiliates and Associates of such Person, is, as of the
close of business on the date of the closing of the initial public offering of
shares of common stock of the Corporation in the fall of 1993, the beneficial
owner of 15% or more of the voting power of the then outstanding Voting Stock at
such time.

                   3N.  The term "voting power" shall mean, with respect to each
outstanding share of capital stock of the Corporation, the number of votes of
which a holder of such share shall be entitled, at the time, to vote generally
in the election of the Directors.
<PAGE>

         PART D - PARD. Powers of the Board of Directors.

         A majority of the Directors of the Corporation, unless there is an
Interested Stockholder, in which case a majority of the Continuing Directors
then in office, shall have the power to determine for the purposes of this
Article V, on the basis of information known to them after reasonable inquiry,
(i) whether a person is an Interested Stockholder, (ii) the number or percentage
of shares of Voting Stock or other equity securities beneficially owned by any
person, (iii) whether a person is an Affiliate or Associate of, or is affiliated
or associated with, another person, (iv) whether the assets which are the
subject of any Business Combination have, or the consideration to be received
for the issuance or transfer of securities by the Corporation or any Subsidiary
in any Business Combination, has, an aggregate Fair Market Value of $5,000,000
or more, (v) whether the requirements of Part B of this Article V have been met
with respect to any Business Combination, and (vi) any other matters of
interpretation arising under this Article V. The good faith determination by the
affirmative vote of a majority of the Directors, or, if there is an Interested
Stockholder, by the affirmative vote of a majority of the Continuing Directors
then in office, on such matters shall be conclusive and binding for all purposes
of this Article V.

         PART E - No Effect on Fiduciary Obligations of Interested Stockholders.

         Nothing contained in this Article V shall be construed to relieve any
Interested Stockholder from any fiduciary obligation imposed by law.

                                   ARTICLE VI
                               STOCKHOLDER ACTION

         Any action required or permitted to be taken by the stockholders of the
Corporation must be effected at a duly called annual or special meeting of such
holders or by a consent in writing signed by the holders of all of the
outstanding shares authorized to vote at such meeting. Except as otherwise
required by law, special meetings of the stockholders of the Corporation may be
called only by (i) the Board of Directors pursuant to a resolution approved by
the affirmative vote of a majority of the Directors then in office, (ii) the
Chairman of the Board, if one is elected, or (iii) the President; provided,
however, that, if at the time of any such call there is an Interested
Stockholder, such call shall also require the affirmative vote of a majority of
the Continuing Directors then in office. Only those matters set forth in the
notice of the special meeting may be considered or acted upon at a special
meeting of stockholders of the Corporation, unless otherwise provided by law.
Advance notice of any matters which stockholders intend to propose for action at
an annual meeting shall be given in the manner provided in the By-Laws.
<PAGE>

                                  ARTICLE VII
                                    DIRECTORS

              1.   General. All power of the Corporation shall be exercised by
or under the direction of the Board of Directors except as otherwise provided
herein or required by law.

              2.   Election of Directors. Election of Directors need not be by
written ballot unless the By-Laws of the Corporation shall so provide.

              3.   Number, Election and Terms.

                   3A.  Except as otherwise fixed pursuant to the provisions of
Article IV hereof relating to the rights of the holders of any class or series
of preferred stock to elect Directors, the number of Directors of the
Corporation shall be fixed exclusively by resolution duly adopted from time to
time by the affirmative vote of at least two-thirds of the Board of Directors.
The Directors, other than those who may be elected by the holders of any class
or series of preferred stock, shall be classified, with respect to the time for
which they severally hold office, into two classes, as nearly equal in number as
possible as determined by the Board of Directors, with one class to be elected
annually.

                   3B.  Commencing at the effective time of the merger of
Strategic Diagnostics Inc. ("SDI") and EnSys Environmental Products, Inc.
("EnSys"), with the Corporation as the surviving corporation, and continuing
through the 1998 annual meeting of stockholders of the Corporation, the Board of
Directors shall consist of seven (7) members. The initial Board of Directors
shall be elected as follows: EnSys and SDI will each select three (3) members of
the Board of Directors and the remaining member of the Board of Directors will
be selected by The Perkin-Elmer Corporation (the "Perkin-Elmer Corporation").
The Directors of the Corporation shall hold office as follows: the Class I
Directors shall hold office for a term expiring at the 1997 annual meeting of
the stockholders and the Class II Directors shall hold office for a term
expiring at the 1998 annual meeting of stockholders, with the members of each
class to hold office until their respective successors are duly elected and
qualified. At each annual meeting of the stockholders of the Corporation,
Directors elected to succeed those whose terms are expiring at that meeting
shall be elected to hold office for a term expiring at the annual meeting of
stockholders held in the second year following the year of their election and
until their respective successors are duly elected and qualified. No decrease in
the number of directors shall shorten the term of any incumbent director.

              4.   Stockholder Nominations of Director Candidates. Except as
otherwise fixed pursuant to the provisions of Article IV hereof relating to the
rights of the holders of any class of series of preferred stock to elect
Directors, advance notice of nominations for the election of Directors, other
than by the Board of Directors or a committee thereof, shall be given in the
manner provided in the By-Laws. Notwithstanding the foregoing, all Class I
Directors holding office at the time of the 1997 annual meeting shall
automatically be nominated, subject to such director's consent, to serve an
additional two (2) year term expiring at the 1999 annual meeting of the
stockholders of the Corporation and all Class II Directors holding office at the
time of the 1998 annual meeting shall automatically be nominated, subject to
such director's consent, to serve an additional two (2) year term expiring at
the 2000 annual meeting of the stockholders of the Corporation.
<PAGE>

              5.   Vacancies and Newly Created Directorships. Except as
otherwise fixed pursuant to the provisions of Article IV hereof relating to the
rights of the holders of any class or series of preferred stock to elect
Directors, any vacancy occurring in the Board of Directors, including any
vacancy created by reason of a newly created directorship resulting in an
increase in the number of directors or any vacancy resulting from death,
resignation, disqualification, removal or other causes, shall be filled solely
by the affirmative vote of a majority of the remaining Directors then in office,
if a quorum is present; provided, however, that, if there is an Interested
Stockholder at the time of such vote, the filling of such vacancy shall also
require the affirmative vote of a majority of the Continuing Directors then in
office. Notwithstanding anything contained herein to the contrary, any Director
that voluntarily leaves office may vote on his or her replacement. Any Director
appointed in accordance with the preceding sentence shall hold office for the
remainder of the full term of the class of Directors in which the new
directorship was created or the vacancy occurred and until such Director's
successor shall have been duly elected and qualified. When the number of
Directors is increase or decreased, the Board of Directors shall determine the
class or classes to which the increased or decreased number of Directors shall
be apportioned. In the event of a vacancy in the Board of Directors, the
remaining Directors, except as otherwise provided by law, may exercise the
powers of the full Board of Directors until the vacancy is filled.

              6.   Removal. Except as otherwise fixed pursuant to the provisions
of Article IV hereof relating to the rights of the holders of any class or
series of preferred stock to elect Directors, any Director (including persons
elected by Directors to fill vacancies in the Board of Directors) may be removed
from office only with cause and by the affirmative vote of at least two-thirds
of the total votes which would be eligible to be cast by stockholders in the
election of such Director at a duly constituted meeting of stockholders called
expressly for such purpose. A Director may not be removed from office without
cause. At least 30 days prior to any meeting of stockholders at which it is
proposed that any Director be removed from office, written notice shall be sent
to the Director whose removal will be considered at the meeting.

                                  ARTICLE VIII
                             LIMITATION OF LIABILITY

         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 General Corporation Law of
Delaware, or (iv) for any transaction from which the Director derived an
improper personal benefit. If the General Corporation Law of Delaware is amended
after the effective date of this Certificate of Incorporation to authorize
corporate action further eliminating or limiting the personal liability of
directors, then the liability of a Director of the Corporation shall be
eliminated or limited to the fullest extent permitted by the General Corporation
Law of Delaware, as so amended.
<PAGE>

         Any repeal or modification of this Article VIII (i) by the stockholders
of the Corporation, or (ii) by an amendment to the General Corporation Law of
Delaware shall not adversely affect any right or protection existing at the time
of such repeal or modification with respect to any acts or omissions occurring
either before or after such repeal or modification of a person serving as a
Director at the time of such repeal or modification.

                                   ARTICLE IX
       STANDARDS FOR BOARD OF DIRECTORS' EVALUATION OF OFFERS OR PROPOSALS


         The Board of Directors of the Corporation, when evaluating any offer or
proposal of any person to (i) make a tender or exchange offer for any equity
security of the Corporation or any subsidiary, (ii) merge or consolidate the
Corporation or any subsidiary with another person, or (iii) purchase or
otherwise acquire all or substantially all of the properties and assets of the
Corporation or any subsidiary, may, in connection with the exercise of its
judgment in determining what is in the best interests of the Corporation and its
stockholders, give due consideration to all relevant factors, including without
limitation, (a) the social and economic effects of acceptance of such offer or
proposal on the employees of the Corporation and its subsidiaries, the
suppliers, creditors, and customers of the Corporation and its subsidiaries, and
the state, region, and communities in which the Corporation and its subsidiaries
operate and are located, and (b) the long-term and short-term interests of the
Corporation and its stockholders, including the possibility that these interests
may be best served by the continued independence of the Corporation.

                                   ARTICLE X
                              AMENDMENT OF BY-LAWS

         The Board of Directors shall have the power to adopt, alter, amend and
repeal the By-Laws of the Corporation. Any By-Laws of the Corporation adopted by
the Directors under the powers conferred hereby may be altered, amended or
repealed by the Directors or the stockholders. Notwithstanding the foregoing or
any other provisions of this Certificate of Incorporation or the By-Laws of the
Corporation to the contrary, such action by the Board of Directors shall require
the affirmative vote of at least two-thirds of the Directors then in office.
Notwithstanding the foregoing or any other provisions of this Certificate of
Incorporation or the By-Laws of the Corporation to the contrary, any action by
the stockholders to alter, amend or repeal the By-Laws of the Corporation shall
require the affirmative vote of at least two-thirds of the total votes eligible
to be cast by stockholders with respect to such alteration, amendment or repeal,
voting together as a single class, at a duly constituted meeting of stockholders
called expressly for such purpose.
<PAGE>

                                   ARTICLE XI
                    AMENDMENT OF CERTIFICATE OF INCORPORATION

         The Corporation reserves the right to repeal, alter or amend this
Certificate of Incorporation in the manner now or hereafter prescribed by
statute and this Certificate of Incorporation, and all rights conferred upon
stockholders herein are granted subject to this reservation. No repeal,
alteration or amendment of this Certificate of Incorporation shall be made
unless the same is first approved by the Board of Directors of the Corporation
pursuant to a resolution adopted by the affirmative vote of a majority of the
Directors then in office, and thereafter approved by the stockholders.