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                                                                  EXHIBIT 10.39b

                                    GUARANTEE



         FOR VALUE RECEIVED, the undersigned hereby unconditionally guarantees
to STANLEY P. DESJARDINS ("Desjardins"), the prompt payment and performance by
SIMULA, INC. ("Simula"), of Simula's payment, performance, and other obligations
(the "Obligations") under that certain Promissory Note dated October 15, 1999 in
the amount of One Million Dollars ($1,000,000) payable by Simula, Inc. to
Desjardins ("Note").

         Upon the occurrence of any event of default under the Obligations,
Desjardins may enforce this Guaranty independently as to the undersigned and
independently of any other remedy or security which Desjardins may at any time
have in connection with the Obligations. The undersigned expressly waives any
right to require Desjardins to proceed against Simula and agrees that Desjardins
may proceed against the undersigned and/or any collateral in such order as
Desjardins shall determine in its sole and absolute discretion.

         The undersigned's total obligation under this Guarantee shall be
payment in the amount of $100,000, only.

         The undersigned hereby irrevocably waives all rights which may have
arisen in connection with this guarantee to be subrogated to any of the rights
(whether contractual, under Title 11 of the United States Code, including
Section 509 thereof, under common law or otherwise) of Desjardins against Simula
or against any collateral security or guarantee or right of offset held by
Desjardins for payment of the Obligations. The undersigned hereby further
irrevocably waives all contractual, common law, statutory or other rights of
reimbursement, contribution, exoneration or indemnity (or any similar right)
from or against Desjardins or any other person which may have arisen in
connection with this guarantee. So long as the Obligations remain outstanding,
if any amount shall be paid by or on behalf of the Simula to the undersigned on
account of any of the rights waived in this paragraph, such amount shall be held
by the undersigned in trust, segregated from other funds of the undersigned, and
shall, forthwith upon receipt by the undersigned, be turned over to Desjardins
in the exact form received by the undersigned to be applied against the
Obligations. The provisions of this paragraph shall survive the term of this
guarantee and the satisfaction in full of the Obligations.

         This Guarantee shall terminate upon the earliest of the following:
         (a)      The payment of the Note and all accrued interest in full;
         (b)      One year from the date hereof; or
         (c)      The voluntary resignation or involuntary termination of the
                  undersigned as an employee of Simula, Inc.

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         Desjardins may not assign his rights and interests under this
Guarantee.

         THIS GUARANTEE HAS BEEN DELIVERED AT PHOENIX, ARIZONA, AND SHALL BE
CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF ARIZONA.
Wherever possible each provision of this guarantee shall be interpreted in such
manner as to be effective and valid under applicable law, but if any provision
of this guarantee shall be prohibited by or invalid under such law, such
provision shall be ineffective to the extent of such prohibition or invalidity,
without invalidating the remainder of such provision or the remaining provisions
of this guarantee.

         SIGNED AND DELIVERED this 2nd day of November, 1999.


                                           /s/ Don Townsend
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                                           Don Townsend



                                           /s/ Nelda Townsend
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                                           Nelda Townsend