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                                  EXHIBIT 10.20




June 26, 1998




Mr. Donald Reiser
5657 Ravenel Lane
Springfield, VA 22151

Dear Don:

As the result of our discussions this week, the Company has accepted your
resignation. We sincerely appreciate your contribution to the Company for the
past sixteen years. Because of the circumstances discussed, the Company has
agreed to the following:

1.   Your termination as an employee of Sensys Technologies is effective at the
     end of the regular work day on July 17, 1998. All authority to discharge
     contracts, agreements, personnel activities, or to perform any duties as an
     employee will be terminated at that time.

2.   You will receive severance pay for the period from July 20, 1998 through
     January 15, 1999 at your regular bi-weekly salary of $5,577.60 less the
     required deductions, payable in accordance with Sensys Technologies Inc.
     normal payroll practices. During this period I ask that you agree to work
     from time to time when reasonably available.

3.   You will receive payment for your excess vacation hours in two equal
     payments on July 15, 1998 and September 15, 1998. Your will be paid for the
     balance of your accrued vacation leave in your final severance check on
     January 29, 1999. In accordance with Company policy, your unused personal
     leave and sick leave have no cash value at separation.

4.   Your health insurance coverage will continue through January 1999 through
     normal payroll deductions. After January 1999, you will be eligible to
     extend coverage at your own expense pursuant to the provisions of the
     Consolidated Omnibus Budget Reconciliation Act (COBRA).

5.   If you wish, you may continue your contributions to the 401(k) through
     January 15, 1999. However, a 401(k) Company match will be made only on
     contributions which you have made through July 17, 1998. If the Company
     makes a discretionary profit sharing contribution this year, it will be
     based on your compensation through July 17, 1998.

6.   Effective July 17, 1998, your vacation and sick leave accruals will cease,
     and group life insurance, and long-term and short-term disability insurance
     coverage will be terminated.

7.   You may continue to use the Company car through September 30, 1998.
     However, you will be responsible for gasoline and telephone expenses after
     July 17, 1998. If you elect to keep the car, the lease must be transferred
     by October 1, 1998.



<PAGE>   2


Mr. Donald Reiser
June 26, 1998
Page 2



8.   A Consulting Agreement will be executed for a one year period starting on
     January 18, 1999 and ending on January 18, 2000, at a daily rate of $700.
     Your security clearances will remain active during this period.

9.   You shall return any telephone and credit cards, building keys, card keys,
     records, reports, proposals, lists, correspondence, specifications,
     drawings, blueprints, sketches, materials, equipment, documents, property,
     or reproductions of any aforementioned items belonging to Sensys
     Technologies Inc. on July 17, 1998.

10.  You shall complete and submit any expense reports by July 17, 1998.

11.  You have previously signed an Agreement with respect to inventions, patents
     and secrecy with the Company. We anticipate that you will continue to abide
     by that agreement. If you should need a copy of this agreement, one will be
     provided to you by Connie Knoernschild.

In order to qualify for the severance pay and continued insurance coverage, you
must complete the attached Release and Settlement Agreement. Please read this
agreement carefully before signing. The agreement advises you to consult with an
attorney before signing. The law under which this release is issued specifies
that you must be granted 21 days in which to sign the agreement and an
additional 7 days in which the agreement may be revoked. You are not required to
wait 21 days before signing the agreement. The severance pay will not begin to
be paid until 7 days after you have signed the agreement.


Sincerely,

SENSYS TECHNOLOGIES INC.


/s/ S.R. Perrino

S.R. Perrino
President

Attachment - Release and Settlement Agreement


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                        RELEASE AND SETTLEMENT AGREEMENT


THIS AGREEENT is made this 17th day of July, 1998 between Donald Reiser
(hereinafter "Employee") and Sensys Technologies, Inc. (hereinafter "Employer").
The Agreement sets forth:

                                    RECITALS

         A.       Employee is employed by Employer; and

         B.       Effective July 17, 1998, Employee's employment with Employer
                  will be retired due to the Employer's decision to request that
                  the Employee retire (hereinafter "retirement date"); and

         C.       Employee and Employer recognize that severance pay would be of
                  assistance to Employee; and

         In consideration of the foregoing and of the promises and the mutual
         covenants contained herein, it is hereby agreed between Employee and
         Employer as follows:


1.       Employer agrees to pay Employee severance pay from July 20, 1998
         through January 15, 1999 (less appropriate withholdings).

2.       Employer also agrees to pay the Employer's cost of medical premiums
         through January 31, 1999.

3.       Employee recognizes that the amounts to be paid pursuant to Paragraphs
         1 and 2 above are in excess of any earned wages or benefits due and
         owing Employee through his retirement date.

4.       In exchange for the good and valuable consideration set forth in
         Paragraphs 1 and 2, Employee agrees to release, waive and discharge any
         and all manner of action, causes of action, claims, rights, charges,
         suits, damages, debts, demands, obligations, attorneys fees, or any and
         all other liabilities or claims of whatsoever nature, whether in law or
         in equity, known or unknown, including, but not limited to any claim
         and/or claim of damages or other relief for tort, breach of contract,
         personal injury, negligence, age discrimination under The Age
         Discrimination In Employment Act of 1967 (as amended), employment
         discrimination prohibited by other federal, state or local laws
         including sex, race, national origin, marital status, age, handicap,
         height, weight, or religious discrimination, and any other claims for
         unlawful employment practices which Employee has claimed or may claim
         or could claim in any local, state or federal forum, against Employer,
         its directors, officers, employees, successors and assigns and its
         parent affiliates and subsidiaries, and all others, as a result of
         Employee's employment at and separation of employment from Employer.

5.       Employee understands that he does not waive rights or claims that may
         arise after the date this Agreement is executed.

6.       Employee further agrees that he has read this Agreement carefully and
         understands all of its terms.

7.       Employee understands and agrees that he is advised to consult with an
         attorney prior to executing this Agreement.

8.       Employee understands and agrees that he has been given 21 days within
         which to consider this Agreement.

9.       Employee understands and agrees that he may revoke this Agreement for a
         period of seven calendar days following the execution of this
         Agreement. The Agreement is not effective until this revocation period
         has expired. Employee understands that any revocation, to be effective,
         must be in writing and either (a) postmarked within seven days of
         execution of this Agreement and addressed to the Human Resources
         Department to the attention of Connie Knoernschild or (b) hand
         delivered to Ms. Knoernschild. Employee understands that if revocation
         is made by mail, mailing by certified mail, return receipt requested is
         recommended to show proof of mailing.



<PAGE>   4


Release and Settlement Agreement
Donald Reiser
Page 2


10.      In agreeing to sign this Release and Settlement Agreement, Employee is
         doing so completely voluntarily and agrees that he has not relied on
         any oral statements or explanations made by Employer or its
         representatives.

11.      Both parties agree to keep the facts, terms, and amount of this
         Agreement confidential and neither party will hereafter disclose any
         information concerning this Agreement to anyone, except to legal and
         accounting advisors and except as may be required by law and as is
         necessary for legitimate enforcement or compliance purposes.

12.      The execution of this Agreement shall not be construed as an admission
         of a violation of any statute or law or a breach of and duty or
         obligation by either party to this agreement.

13.      Both parties agree that this Agreement shall be governed by, and
         interpreted in accordance with the laws of the State of Virginia.

14.      In the event that a provision of this Agreement, or any portion
         thereof, is judicially determined to be unenforceable as written, such
         provision shall be construed so as to give it the maximum effect
         permitted under applicable law.

15.      This agreement, (including the terms set forth in the attached letter
         dated June 26, 1998) constitutes the entire agreement between Sensys
         Technologies Inc. and Donald Reiser with respect to the subject matter
         of this Agreement and supersedes all prior negotiations and agreements,
         whether written or oral. This Agreement may not be altered or amended
         except by a written document executed by all of the parties.

                                           EMPLOYEE:


/s/ C. Knoernschild                        /s/ Donald Reiser
---------------------------------          ------------------------------------
Witness                                    Donald Reiser


Date 6-29-98
---------------------------------
                                           SENSYS TECHNOLOGIES INC.:


/s/ C. Knoernschild                        /s/  S.R. Perrino
---------------------------------          ------------------------------------
Witness                                    By:
                                           Title: President
                                           ------------------------------------

Date 6-9-98
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