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                                                                   Exhibit 10.15
                        [TASER INTERNATIONAL LETTERHEAD]

                                PROMISSORY NOTE


Amount of Note ($): $75,000 Cash
City: Scottsdale, State: Arizona
Date: July 1, 1999


     FOR VALUE RECEIVED the undersigned jointly and severally promise(s) to pay
to the order of:
     Malcolm Sherman, currently residing in Scottsdale, Arizona
the principal sum of:
     Seventy-Five thousand & no/100 ($75,000.00) dollars together with interest
thereon from date at the rate of:
     9.18% Per Annum
until maturity, said principal and interest shall be paid in 24 equal monthly
payments of $3,757.37, beginning on August 15, 1999 with the last payment
submitted on July 15, 2001. (Please see attached Loan Amortization).

     Each maker and endorser severally waives demand, protest and notice of
maturity, non-payment or protest and all requirements necessary to hold each of
them liable as makers and endorsers and, should litigation be necessary to
enforce this note, each maker and endorser waives trial by jury and consents to
the personal jurisdiction and venue of a court of subject matter jurisdiction
located in the State of Arizona, and County of Maricopa.

     Each maker and endorser further agrees, jointly and severally, to pay all
costs of collection, including a reasonable attorney's fee in case the principal
of this note or any payment on the principal or any interest thereon is not paid
at the respective maturity thereof, or in case it becomes necessary to protest
the security hereof, whether suit be brought or not.

     This note is to be construed and enforced according to the laws of the
State of Arizona; upon default in the payment of principal and/or interest when
due, the whole sum of principal and interest remaining unpaid shall, at the
option of the holder, become immediately due and payable and it shall accrue
interest at the highest rate allowable by law, or, if no highest rate is
otherwise indicated, at ten (10%) percent, from the date of default.

     Default shall include, but not be limited to non-payment within ten (10)
days from the due date set out herein.

     Unless specifically disallowed by law, should litigation arise hereunder,
service of process therefore may be obtained through certified mail, return
receipt requested; the parties hereto waiving and all rights they may have to
object to the method by which service was perfected.

                                                                          /s/MWS
                                                                          /s/TPS


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Taser International, Inc. herein acknowledges and agrees to the following,
regarding the herein described Promissory Note.

     A. The monies being borrowed are to secure tooling and equipment for that
        product as described in the enclosed attachment, marked "A" and listed
        as "Steman International Procurement, Quotation No: 98Q01-1-AT," Taser
        International, Inc. purchase order numbers: 021025-00, 021026-00,
        021027-00, 021028-00, 021024-00 additionally known as "The Advanced
        Taser." Additional components as secured by Taser International, Inc. to
        complete the production of this product are included in the UCC filing
        and are described as electrical components, finished product or
        packaging.

     B. Taser International, Inc. agrees to the tooling and components as
        purchased by the funds of this Promissory Note being subject to a UCC
        filing in favor of Malcolm W. Sherman i.e., lender. Said UCC filing to
        be valid for the full period of the listed payment schedule. Taser
        International, Inc. agrees to the UCC filing of this lien and its
        permission is granted for a "floating lien" to be issued to Malcolm W.
        Sherman.

     C. Taser International, Inc. agrees and acknowledges that they have no
        right to sell, transfer, assign, sublease or encumber the equipment or
        this agreement or material covered under this agreement.

     D. All cost relative to the filing of the above listed UCC filings are to
        be born by Taser International, Inc.


All matters pertinent to this Agreement (including its interpretation,
application, validity, performance and breech), shall be governed by, construed
and enforce in accordance with the laws of the State of Arizona. The parties
herein waive trial by jury and agree to submit to the personal jurisdiction and
venue of a court of subject matter jurisdiction located in Maricopa County,
State of Arizona. In the event that litigation results from or arises out of
this Agreement or the performance thereof, the parties agree to reimburse the
prevailing party's reasonable attorney's fees, court costs, and all other
expenses, whether or not taxable by the court as costs in addition to any other
relief to which the prevailing party may be entitled. In such event, no action
shall be entertained by said court or any court of competent jurisdiction if
filed more than one year subsequent to the date of the cause(s) of action
actually accrued regardless of whether damages were otherwise as of said time
calculable.

                           TASER INTERNATIONAL, INC.
                           -------------------------
                                  Corporation

/s/ Malcolm W. Sherman                       By: /s/ Patrick Smith
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Payee - Signature                                President - Signature


M. W. Sherman                                    Patrick Smith
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Payee Name Printed                               President

                                                  Corporate Seal
Attest: /s/ Thomas P. Smith                      [Corporate Seal]
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Treasurer - Signature


Thomas P. Smith
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Treasurer