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                                                                   EXHIBIT 10.15


                              STOCK SALE AGREEMENT


THIS AGREEMENT, dated February 23, 1999, is between Mutsuo Tanaka, Individually
("Buyer"), and Ultrak, Inc., a Delaware corporation ("Ultrak").

                                    RECITALS

         Ultrak owns 45,444 shares (the "Shares") of the issued and outstanding
common stock, (Y)500 par value of Securion o 24 Co., Ltd., a Japanese
Corporation ("Securion Stock"). Ultrak desires to sell the Shares to Buyer, and
Buyer desires to purchase the Shares from Ultrak, in accordance with the terms
of this Agreement.

         NOW, THEREFORE, in consideration of the foregoing and the terms of this
Agreement, the receipt and adequacy of which are hereby acknowledged, the
parties hereto, intending to be legally bound, hereby covenant and agree as
follows:

                               ARTICLE I: THE SALE

         1.01. The Sale. On the terms and subject to the conditions set forth
herein, at the Closing (as hereinafter defined) Ultrak agrees to sell to Buyer,
and Buyer agrees to purchase from Ultrak, the Shares.

         1.02. Purchase Price. The purchase price to be paid to Ultrak by Buyer
for the Shares shall be (Y)4,950 per share or an aggregate of (Y)224,947,800
(the "Purchase Price"), and subject to paragraph 6.03 the Purchase Price shall
be paid by wire transfer of funds into Ultrak's bank account in Japan described
on Schedule A attached hereto and in accordance with paragraph 5.02 below.

         1.03. Closing. The closing of the transactions contemplated by this
Agreement (the "Closing") shall take place on February 26, 1999, at 10:00
o'clock a.m., Central Standard Time, via facsimile. The day on which the Closing
occurs is herein referred to as the "Closing Date."

         1.04. Further Assurances. After the Closing, Buyer shall execute and
deliver such additional documents and take such additional actions as Ultrak may
reasonably deem to be practical and necessary or advisable in order to
consummate the transactions contemplated by this Agreement or to vest more fully
in Buyer the ownership of the Shares.

              ARTICLE II: REPRESENTATIONS AND WARRANTIES OF ULTRAK

         Ultrak represents and warrants to Buyer that the following are true and
correct:

        2.01. Organization. Ultrak is a corporation duly organized and validly
existing under Delaware law and has the corporate power and authority to own or
hold under lease its properties and assets and to carry on its business as it is
now being conducted.

        2.02. Corporate Records. Copies of Ultrak's Articles of Incorporation  
(the "Charter") and Bylaws and all amendments thereto will be made available 
upon request to Buyer.



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       2.03 Corporate Authority. Ultrak has the corporate power to enter into
this Agreement and to carry out its obligations hereunder. The execution and
delivery of this Agreement and the consummation of the transactions contemplated
hereby have been duly and validly authorized by all necessary corporate action
on the part of Ultrak and no other corporate proceedings on the part of Ultrak
are necessary to authorize this Agreement or the transactions contemplated
hereby. This Agreement has been duly and validly executed and delivered by
Ultrak and, assuming this Agreement constitutes a valid and binding agreement of
Buyer, this Agreement constitutes a valid and binding agreement of Ultrak,
enforceable against Ultrak in accordance with its terms. Neither the execution
and delivery of this Agreement by Ultrak nor the consummation of the
transactions contemplated hereby by Ultrak will: (a) violate or conflict with
any provision of the Charter or Bylaws of Ultrak, or (b) violate or conflict
with any law, regulation, permit, authorization, franchise, license, judgment,
order, writ, injunction or decree of any court or governmental body of any
jurisdiction, in each case as such is related to Ultrak or its assets.

       2.04 Consents. No authorization, consent, approval, permit or license of,
or filing with, any governmental or public body or authority, any lender or
lessor or any other person or entity is required to authorize, or is required in
connection with, the execution, delivery, and performance of this Agreement or
the agreements contemplated hereby on the part of Ultrak.

       2.05. Shares. The Shares are duly authorized, validly issued, fully paid,
and nonassessable. There are no preemptive rights with respect to the Shares. To
the best of Ultrak's knowledge and belief, there are no outstanding
subscriptions, options, warrants, rights, or other arrangements or commitments,
whether express or implied, obligating Ultrak to transfer the Shares to any
third party. Ultrak has not granted any liens on the Shares.

       2.06 Brokers and Finders. Neither Ultrak nor any of their officers,
directors, affiliates, representatives, or agents has employed any broker,
finder, or investment bank or incurred any liability for any investment banking
fees, financial advisory fees, brokerage fees, or finders' fees in connection
with the transactions contemplated hereby.

       2.07 Interference with Business. Ultrak warrants not to interfere with or
obstruct, directly or indirectly, or through ISCO, Mr. Kiyohide Mizuno or Mr.
Kakugawa, in Securion o 24 Co., Ltd.'s business arrangements with Ace Denken and
Glory Shoji, which Buyer alleges have been already established by binding
agreement. However, Ultrak cannot be held responsible for the actions or conduct
of these or any other parties in business dealings other than the actions and
conduct of Mr. Mizuno who acts as Ultrak's independent sales representative in
Japan.

              ARTICLE III: REPRESENTATIONS AND WARRANTIES OF BUYER

         Buyer represents and warrants to Ultrak that the following are true and
correct:

        3.01. Corporate Authority. This Agreement has been duly and validly
executed and delivered by Buyer and, assuming this Agreement constitutes a valid
and binding agreement of Ultrak, this Agreement constitutes a valid and binding
agreement of Buyer, enforceable against Buyer in accordance with its terms.
Neither the execution and delivery of this Agreement nor the consummation of the
transactions contemplated hereby will: (x) violate or conflict with, or result
in the breach or termination of, or otherwise give any other contracting party
the right to terminate, or constitute a default (or an event which, with the
lapse of time, or the giving of notice, or both, will constitute a default)
under, any contract, license, other instrument or 


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commitment to which Buyer is a party or by which Buyer is bound, or result in
the creation of any lien, charge or encumbrance upon the properties or assets of
Buyer pursuant to the terms of any such contract, license, instrument or
commitment; or, (y) violate or conflict with any law, regulation, permit,
authorization, franchise, license, judgment, order, writ, injunction or decree
of any court or governmental body of any jurisdiction, in each case as such is
related to Buyer or its assets.

         3.02. Consents. No authorization, consent, approval, permit or license
of, or filing with, any governmental or public body or authority, any lender or
lessor or any other person or entity is required to authorize, or is required in
connection with, the execution, delivery, and performance of this Agreement or
the agreements contemplated hereby on the part of Buyer.

         3.03 Brokers and Finders. Neither Buyer nor any representative or agent
of Buyer has employed any broker, finder, or investment bank or incurred any
liability for any investment banking fees, financial advisory fees, brokerage
fees, or finders' fees in connection with the transactions contemplated hereby.

                     ARTICLE IV: RELEASE AND INDEMNIFICATION

         4.01 By Buyer. Buyer agrees to release, indemnify and forever hold
harmless Ultrak, its parent, subsidiaries, affiliates, divisions, officers,
directors, employees, agents and assigns from any loss or damages (including
reasonable attorney's fees) incurred by Ultrak as a result of claims, suits or
demands of any kind, including those of third parties for any loss or damage, to
the extent such loss or damage is caused by or results from the acts or
omissions of Buyer or its employees or agents; provided, however, that this
release, indemnification and hold harmless shall not apply to warranty claims
relating to products sold by Ultrak to Buyer as per Section 5 of that certain
non-exclusive Distributorship Agreement dated October 6, 1998.

         4.02 By Ultrak. Ultrak agrees to release, indemnify and hold harmless
Buyer, his employees, agents and assigns from any loss or damages (including
reasonable attorney's fees) incurred by Buyer as a result of claims, suits or
demands of any kind, including those of third parties for any loss or damage, to
the extent such loss or damage is caused by or results from the acts or
omissions of Ultrak or its employees or agents; provided, however, that this
release, indemnification and hold harmless shall not apply to warranty claims
relating to products sold by Ultrak to Buyer as per the terms of that certain
non-exclusive Distributorship Agreement dated October 6, 1998.

                          ARTICLE V: CLOSING DELIVERIES

         5.01. Deliveries by Ultrak. Ultrak deliver to Abe & Matsutome Law
Office, Attention: Wada Nobuhiro, the share certificates representing the Shares
and all such documents as may be reasonably required by Buyer (including but not
limited to, Ultrak's application for approval by the Board of Directors of
Securion o 24 Co., Ltd. Of the transfer of the Shares hereunder) on or before
February 25, 1999 (Japan time). Buyer or his agent may examine such share
certificates and documents prior to remittance of the Purchase Price. Ultrak
shall procure the Abe & Matsutome deliver to Buyer the Shares as represented by
the share certificates and documents upon receipt by Abe & Matsutome of copies
of documents evidencing the remittance of the Purchase Price by Buyer.

         5.02. Deliveries by Buyer. Buyer shall deliver to Ultrak the Purchase
Price via wire transfer within three (3) business days after February 26, 1999
(Japan time).


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                            ARTICLE VI: MISCELLANEOUS

        6.01. Modification, Amendment and Waiver. This Agreement may not be
modified unless such modification is in writing and signed by both parties
hereto. No waiver of any term of this Agreement shall be enforceable unless in
writing and signed by the party against which it is sought to be enforced. The
waiver by any party of a breach of any provision of this Agreement shall not
operate or be construed as a waiver of any subsequent breach by such other
party.

        6.02 Expenses. Each party hereto shall bear its own expenses incurred in
connection with this Agreement and the consummation of the transactions
contemplated hereby.

        6.03 Legal Fees. Ultrak shall reimburse Buyer for up to $7,500.00 US of
legal costs incurred by Buyer at the Hashidate Law Office. This amount shall be
converted to Japanese Yen on the Closing date and then credited against the
purchase price set forth in paragraph 1.02 above.

        6.04. Counterparts. This Agreement may be executed in two or more
counterparts, all of which will be considered the same agreement and faxed
copies of manually executed signature pages to this Agreement will be fully
binding and enforceable without the need for delivery of the manually executed
signature page.

        6.05. Governing Law. THE INTERNAL LAWS (AND NOT THE CONFLICTS OF LAWS 
RULES) OF CALIFORNIA GOVERN THIS AGREEMENT.

        6.06. Notices. All notices hereunder will be in writing and will be
deemed given if delivered by hand (or recognized international courier or
delivery service) or mailed by registered or certified air mail (return receipt
requested) to the parties at the addresses set forth beside their signatures (or
at such other addresses for a party as will be specified by like notice) and
will be deemed given on the date on which so hand-delivered or on the sixth
business day following the date on which so mailed to the address set forth
opposite the name and signature block for each party to this Agreement.

         6.07 Severability. If any provision of this Agreement is held to be 
illegal, invalid, or unenforceable, such provision shall be fully severable, and
this Agreement shall be construed and enforced as if such illegal, invalid, or
unenforceable provision were never a part hereof; the remaining provisions
hereof shall remain in full force and effect and shall not be affected by the
illegal, invalid, or unenforceable provision or by its severance; and in lieu of
such illegal, invalid, or unenforceable provision, there shall be added
automatically as part of this Agreement, a provision as similar in its terms to
such illegal, invalid, or unenforceable provision as may be possible and be
legal, valid, and enforceable.

       6.08. Assignments; Entire Agreement; Headings. This Agreement shall not
be assignable by operation of law or otherwise. Any attempted assignment of this
Agreement shall be void. This Agreement, the Schedules attached hereto, and the
Exhibits attached hereto constitute the entire agreement, and supersede all
other prior agreements and understandings, both written and oral, between the
parties, or any of them, with respect to the subject matter hereof. All
Schedules, Exhibits, and documents and agreements referred to herein or attached
hereto are fully and completely incorporated herein effective as of the first
reference herein. The headings contained in this Agreement are for reference
purposes and will not affect in any way the meaning or interpretation of this
Agreement. Use of "herein," "hereof" or similar terms refer to this 

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Agreement as a whole. The use of any term denoting a masculine, feminine, or
neuter gender shall include all such genders.

        6.09. Arbitration. ANY DISPUTE OR CLAIM RELATING TO THIS AGREEMENT SHALL
BE FINALLY SETTLED BY ARBITRATION IN ACCORDANCE WITH THE RULES OF THE AMERICAN
ARBITRATION ASSOCIATION, WHICH RULES ARE DEEMED TO BE INCORPORATED HEREIN BY
REFERENCE. ANY SUCH ARBITRATION SHALL BE HELD IN LOS ANGELES, CALIFORNIA,
U.S.A., AND THE LANGUAGE TO BE USED IN THE ARBITRATION PROCEEDING SHALL BE
ENGLISH. JUDGMENT UPON THE AWARD RENDERED BY THE ARBITRATOR MAY BE ENTERED IN
ANY COURT HAVING JURISDICTION THEREOF.

         6.10. Shareholders Agreement. That certain Shareholders Agreement dated
August 21, 1997 between Buyer and Ultrak, shall be terminated as of February 26,
1999, conditioned upon consumation of the Closing contemplated in paragraph 1.03
above.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and delivered as of the date first above written.

ULTRAK, INC                                         Mutsuo Tanaka
1301 Waters Ridge Drive                             c/o SECURION o 24 Co., LTD
Lewisville, Texas 75057    USA                      5F Sumitomo Seimei Bldg.
12-7 Asaji-Cho, Hachioji-City                       Tokyo, 192 Japan
                                                              



By: /s/ GEORGE K. BROADY                            By: /s/ MUTSUO TANAKA
   ---------------------------                         ------------------------
      George K. Broady                              Mutsuo Tanaka, Individually
      Chief Executive Officer





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                                   Schedule A


   Buyer should instruct their bank in Japan to deliver Yen to:


   Bank:         Bank of Tokyo-Mitsubishi Ltd.
                 Tokyo, Japan

   Swift:        BOTKJPJT

   For the account of Bank One International Corporation

   Account Number:                       6530410454

   To further credit the account of Ultrak Operating, L.P.

   Account Number:                       1570699635

       NOTE: PLEASE WIRE ADVICE ATTENTION FOREIGN EXCHANGE REFERENCE: DALLAS, TX




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