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                                                              Agreement No.  043


                                                                  EXHIBIT 10.31 


                            CENTRUM INDUSTRIES, INC.

                             STOCK OPTION AGREEMENT


         THIS AGREEMENT is made as of this 21st day of July, 1997, by and
between Centrum Industries, Inc., a Delaware corporation ("Centrum") and
Timothy M. Hunter("Employee").

         NOW THEREFORE, in consideration of the mutual covenants contained in
this Agreement, the parties hereto agree as follows:

         SECTION 1 - GRANT OPTION.  Centrum hereby grants to Employee the right
and option to purchase from it, on the following terms and conditions, all or
any part of an aggregate of Fifty Five Thousand Six Hundred Seventy One
(55,671) shares of Centrum's common stock $.05 par value (the "Shares").  The
purchase price for all Shares shall be $2.00 per share, exercisable and payable
as hereinafter provided.  The price per share represents the fair market value
for these shares as of this date, as determined by Centrum's Board of
Directors.

         SECTION  2 - EXERCISE OF OPTION; CHANGE OF CONTROL.  The Employee may
elect to exercise the option at any time.  Notwithstanding the above, if
Centrum's officers or directors execute a letter of intent (binding or
non-binding) by which Centrum will become a party to a transaction which will
effect a "Change of Control" of Centrum, Employee must exercise his/her options
within the thirty (30) day period following the date of notice to Employee that
a letter of intent has been entered into, or else the option and all rights
granted by this Agreement, to the extent those rights have not been exercised,
will terminate and become null and void.  No partial exercise of such option
may be for less than one  (1)  full Share.  For purposes of this Agreement
"Change of Control" shall be effected if (i) Centrum merges with or into or
consolidates with another corporation following the requisite approval of the
shareholders of Centrum of such merger or consolidation and, after giving
effect to such merger or consolidation, less than fifty-one (51%) of the then
outstanding voting securities of the surviving or resulting corporation
represent or were issued in exchange for voting securities of Centrum
outstanding immediately prior to such merger or consolidation;  (ii)  there is
a sale, lease, exchange or other transfer (in one transaction or a series of
related transactions) of all or substantially all the assets of Centrum
following the requisite approval of the shareholders of Centrum of such
transaction or series of transactions; or  (iii)  the requisite approval of the
shareholders of Centrum is obtained to approve any plan or proposal for the
liquidation or dissolution of Centrum.  The option shall be exercisable only by
Employee during his/her lifetime and only if Employee was a employee of Centrum
or a Centrum affiliate on the date three (3) months prior to the date of
exercise.  If Employee is disabled within the meaning of Section 22(e)(3) of
the Internal Revenue Code of 1986, as amended  (the "Code"),  the reference to
the three (3) month period above shall be read as one (1) year.
        



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                                                              Agreement No.  043


         SECTION  3 - METHOD OF EXERCISE.  The option granted under this
Agreement shall be exercisable as provided above, upon written notice to
Centrum and the payment in cash to Centrum of the full purchase price of the
Shares which the Employee elects to purchase.
        
         SECTION  4 - TERMINATION OF EMPLOYMENT.  In the event that a Employee
shall cease to be employed by Centrum or a Centrum affiliate, whether
voluntarily or involuntarily, for any reason other than death or disability,
all of Employee's rights to further exercise his/her option(s) shall expire
three (3) months after the date of termination of employment; provided,
however, that no option shall be exercisable after the expiration date set
forth in Section 6.  A leave of absence with the express written consent of
Centrum shall not be considered termination of employment for purposes of this
Section 4.
        
         SECTION  5 - DEATH OR DISABILITY OF EMPLOYEE.  In the event of the
death or disability of an Employee while employed by Centrum or a Centrum
affiliate, his/her right to purchase Shares may be exercised  (to the extend
that Employee was entitled to do so at the date of his/her death or disability) 
by him/her or, in the case of the death of Employee, by his/her personal
representative or by any person or persons who shall have acquired the option
directly from Employee by will or by the laws of descent and distribution, at
any time within three (3) months after the date of his/her death or disability;
provided that if Employee is disabled as defined in Section 2 of this
Agreement, the three (3) month period referred to above shall be read as one 
(1) year.  Notwithstanding anything herein to the contrary, no option shall be
exercisable after the expiration of the term of the option set forth in Section
6.
        
         SECTION  6 - TERMINATION OF OPTION.  The option and all rights granted
by this Agreement, to the extent those rights have not been exercised will
terminate and become null and void at 5:00 p.m. on July 21, 2007.
        
         SECTION  7 - SHARES AS INVESTMENT.  By accepting this option, the
Employee acknowledges that any and all Shares purchased pursuant to the
exercise of the option under this Agreement shall be acquired for investment
and not for distribution, and upon the delivery of any and all of the Shares
due to the exercise of the option granted hereunder, the Employee shall deliver
to Centrum a representation in writing and in a form acceptable to Centrum that
such Shares are being acquired in good faith for investment and not for
distribution.  This Section 7 shall not apply in the event that the Shares have
been registered pursuant to the Securities Act of 1933 and applicable state
securities laws.
        
         SECTION  8 - RESTRICTIONS ON SHARES.  Initially the Shares issued
pursuant to the exercise of the option granted in Section 1 may not be
registered under federal securities laws or the securities of any state and
may, therefore, be deemed restricted and certain restrictions will be
applicable upon the resale of such security.  Each Share may, upon issuance,
contain a restrictive legend in substantially the following form:
        

            The common stock represented by this certificate has not been
            registered under the Securities Act of 1933, as amended




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                                                              Agreement No.  043


          or under the securities laws of any state.  Each holder desiring
          to transfer the common stock must furnish Centrum with
          a written opinion reasonable satisfactory to Centrum in the
          form and substance from counsel reasonable satisfactory to
          Centrum by reason of experience to the effect that the holder
          may transfer the common stock as desired without registration
          under the Securities Act or the securities laws of any state.

It is Centrum's present intention to file a registration statement with the
Securities and Exchange Commission to register this option and the underlying
Shares in the near future.  This Section 8 will not apply in the event that the
Shares have been registered pursuant to the Securities Act of 1933 and
applicable state securities laws.

         SECTION  9 - DILUTION OR OTHER AGREEMENT.  In the event that
additional Shares are issued pursuant to a stock split or a stock dividend, the
number of Shares then covered by each outstanding option granted hereunder
shall be increased proportionately with no increase in the total purchase price
of the Shares then so covered.  If the issued and outstanding Shares are
reduced by a reverse stock split or other combination of Shares, (other than
by a transaction described in Section 2 of this Agreement), the number of
Shares then covered by each outstanding option granted hereunder shall be
reduced proportionately with no reduction in the total price of the Shares then
so covered.  In the event that Centrum should transfer assets to another
corporation and distribute the stock of such other corporation without the
surrender of Shares, and if such distribution is not taxable as a dividend and
no gain or loss is recognized by reason of Section 355 of the Code, or some
similar section, then the total purchase price of the Shares shall be reduced
by an amount which bears the same ratio to the total purchase price then in
effect as the market value of the stock distributed with respect to the Shares
immediately following the distribution, bears to the aggregate of the market
value of such time of a Share and the stock distributed in respect thereof.  No
fractional shares shall be issued, and any fractional Shares resulting from the
computations pursuant to this Section 9, shall be eliminated from the option. 
No adjustment shall be made for cash dividends or the issuance to stockholders
of rights to subscribe for additional Shares or other securities.
        
         SECTION  10 - RIGHT OF SHAREHOLDER.  The Employee shall not have any
rights or privileges of a shareholder of Centrum in respect with the Shares
transferable upon exercise of the option granted under this Agreement, unless
and until certificates representing such Shares shall have been endorsed,
transferred, and delivered and the transferee has caused his/her name to be
entered as the shareholder of record on the books of Centrum.
        
         SECTION  11 - NON-TRANSFERABILITY.  The option shall not be
transferable and the option may be exercised, during the lifetime of the
Employee only by him/her.  Except as specifically provided in this Agreement,
the option may not be assigned, transferred, pledged or hypothecated in any
way, shall not be assignable by operation of law, including but not limited to
a decree in a domestic relations proceeding, and shall not be subject to
execution, attachment or similar process.  Any attempted assignment, transfer,
pledge, hypothecation or other disposition
        


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                                                              Agreement No.  043


of the option, and the levy of any execution, attachment, or similar process
upon the option in violation of this Agreement, shall be null and void and
without effect.

         SECTION  12 - AFFILIATE.  As used herein, the term "affiliate" shall
mean any present or any future corporation which would be deemed an affiliate
of Centrum in Rule 12b-2 of the regulations promulgated pursuant to the
Securities Exchange Act of 1934.
        
         SECTION  13 - NOTICES.  Any notice to be given under the terms of this
Agreement shall be addressed to Centrum in care of its President at 6135 Trust
Drive, Suite 104A, Holland, Ohio 43528 with a copy to John W. Hilbert II, Esq.,
Fuller & Henry P.L.L., One SeaGate, 17th Floor, P.O. Box 2088, Toledo, Ohio
43603 and any notice to be given to Employee shall be addressed to him/her at
the address set forth beneath his/her signature below, or at such other address
as either party may hereafter designate in writing to the other.  Any such
notice shall be deemed duly given when mailed by prepaid regular, registered,
or certified mail.
        
         SECTION  14 - BINDING EFFECT.  This Agreement shall be binding upon
Employee and his/her executors administrators, and representatives and assigns,
and upon Centrum and its successors and assigns.
        
         IN WITNESS WHEREOF, the parties have executed this Agreement on the
date first set forth above.


                                     CENTRUM INDUSTRIES, INC.



                                     By: /s/ George H. Wells
                                        --------------------------------------- 
                                        George H. Wells, Chairman of The Board,
                                        Chief Executive Officer and President


                                     "EMPLOYEE"


                                     /s/ Timothy M. Hunter
                                     ------------------------------------------


                                     Employee's Address for Notice Purposes:


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