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                                                                       EXHIBIT 7

                              CONVERTIBLE DEBENTURE
                               3Si HOLDINGS, INC.


         3Si Holdings, Inc., a corporation duly organized and existing under the
laws of the State of Wyoming (the "Company"), for value received, hereby
promises to pay to Jerome K. Thorson, of Boulder, Colorado, the holder hereof
(the "Holder"), the principal sum of One Hundred Thousand Dollars ($100,000)
together with interest at six and one-half percent (6-1/2%) per annum. Interest
shall be payable monthly, on the first day of each successive month hereafter
until the Maturity Date, and shall be adjusted monthly, based on increases or
decreases in the publicly announced prime lending rate for GMAC, Denver,
Colorado. All unpaid principal and accrued interest, if any, shall be payable in
full on the one year anniversary date hereof (the "Maturity Date") upon
presentation and surrender of this Convertible Debenture at the office of the
Company.

         This Convertible Debenture is issued by the Company and delivered to
Holder upon the following terms and conditions:

         1. PREPAYMENT. This Convertible Debenture is subject to prepayment in
whole or in part at any time at the option of the Company. In the case of any
prepayment of less than the total principal amount outstanding, the prepayment
shall be applied first to the interest owed and then to the principal
outstanding. Prepayment shall not preclude Holder from exercising its conversion
privileges as described herein.

         2. CONVERSION. Subject to the provisions hereof, the Holder of this
Convertible Debenture has the right, at his option, at any time after (a) one
hundred eighty (180) days from the date hereof, but prior to the Maturity Date
hereof, or (b) upon notice from the Company of prepayment, to convert the unpaid
principal amount hereof into Common Shares of the Company, as such shares shall
be constituted at the date of conversion, on such terms as shall be mutually
agreed between Holder and the Board of Directors of the Company, taking into
account the then market price of the Company's stock (the mean between the bid
and asked price of the stock as quoted in the OTC pink sheets on the conversion
date), and other factors deemed relevant by the Board to be in the best
interests of the Company and its shareholders; provided, that in any


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event the price on such conversion shall not be less than the per share price
received by the Company for any similar equity sale of stock by the Company
pursuant to a private (non-public) offering of the Company's stock, if any, to a
third party, in an arm's-length transaction during the period from the date of
this Convertible Debenture until such conversion.

         On such conversion date both the Company and the Holder shall mutually
be responsible for, and shall mutually warrant and represent that all material,
current, information regarding the Company has been publicly disclosed for at
least five (5) business days prior to such conversion. Conversion shall be made
by Holder's written notice of his election to convert, delivered with this
Convertible Debenture to the office of the Company, accompanied by an instrument
of transfer in form satisfactory to the Company, executed by the Holder or his
duly authorized agent. No adjustments in respect of interest or dividends will
be made upon any conversion. No fractional shares or scrip representing
fractional shares will be issued upon any conversion, but an adjustment in cash
will be made in respect of any fraction of a share which would otherwise be
issuable upon the conversion.

         3. TRANSFERABILITY. This Convertible Debenture shall not be
transferable by Holder; provided, that upon Holder's death prior to the Maturity
Date, or prior to conversion, it shall pass to Holder's estate, and to his heirs
or designated beneficiaries thereunder, and shall be subject to all of the terms
and conditions hereof.

         4. SUBORDINATION. The indebtedness evidenced by this Convertible
Debenture is subordinate and subject in right of payment to the prior payment in
full of all senior indebtedness of the Company as set forth in EXHIBIT A hereto,
and the Holder of this Convertible Debenture, by his acceptance hereof, agrees
to and shall be bound by all the provisions hereof relating to such
subordination.


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         5. MODIFICATION. The Company and the Holder may hereafter modify or
amend the terms of this Convertible Debenture, by their mutual written consent;
provided, however, that no such written modification shall increase or decrease
the principal amount, the rate of interest, the price of conversion of this
Convertible Debenture into Common Shares, or the rights of the senior
indebtedness of the Company to which this Convertible Debenture is expressly
subordinated.

         6. WAIVER. The Holder may, at his sole option, waive any default by the
Company under this Convertible Debenture, subject to such defaults being cured
to his sole satisfaction upon terms acceptable to him. Any such consent or
waiver by the Holder of this Convertible Debenture shall be conclusive and
binding upon such Holder, but shall not be deemed a waiver as to any other, or
future defaults.

         7. PRINCIPAL OBLIGATION. No reference herein to Holder's right to waive
defaults or to the subordination of this Convertible Debenture to the Company's
senior indebtedness shall alter or impair the obligation of the Company, which
is absolute and unconditional, to pay to Holder the principal of and interest on
this Convertible Debenture at the place, at the respective times, at the rate,
and in cash, or in Common Stock of the Company, as herein prescribed.

         8. CORPORATE OBLIGATION. No recourse under or upon any obligation,
covenant, or agreement contained in this Convertible Debenture shall be had
against any shareholder, officer, or director of the Company or of any successor
corporation; it being expressly understood by the Holder that this Convertible
Debenture is solely a corporate obligation of the Company, and that any and all
personal liability is hereby expressly waived and released by the Holder hereof
by the acceptance of this Convertible Debenture and as a part of the
consideration for the issue hereof.

         9. EXEMPTION UNDER APPLICABLE SECURITIES LAWS. The Holder acknowledges
that this Convertible Debenture is issued to him by the Company without
registration, either under the 1933 Securities Act or any applicable state
securities law, pursuant to applicable exemptions from such registration, based
upon the fact that the Holder: (a) is an Accredited Investor, as that term is
defined under such applicable securities law; (b) is an officer and


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director, and therefore an affiliate of the Company; (c) has available to him
through his access as an insider of the Company and through his access to and
review of all periodic reports filed with the SEC by the Company as a public,
reporting company, all relevant material information considered by him necessary
to make an informed investment decision; and (d) can therefore fend for himself
as a sophisticated, experienced investor able to bear the full risk of loss of
his investment in the Company.

         10. MISCELLANEOUS PROVISIONS.

         10.1 BINDING NATURE. This Convertible Debenture shall be binding upon
the Company, its successors and assigns, and shall inure to the benefit of the
Holder hereof, his successors and assigns as provided herein, subject however,
to the provisions of Section 3 above.

         10.2 COSTS OF COLLECTION. The Company hereby agrees, if this
Convertible Debenture is placed in the hands of any attorney for collection, to
pay Holder's reasonable attorneys' fees and other costs of collection as
permitted by law.

         10.3 WAIVER. The Company hereby waives demand for payment,
presentment, notice of dishonor, notice of non-payment, diligence in collection,
grace period, notice and protest.

         10.4 Remedies Upon Default. The use of any remedy by the Holder hereof
will not constitute a waiver of the right to use any other remedy provided at
law.

         10.5 Extension. Holder's extension of time for payment of this
Convertible Debenture, if given by Holder at his sole option, shall not release
or modify the liability of the Company hereunder.

         10.6 Governing Law. This Convertible Debenture and any disputes arising
or relating to this Convertible Debenture and/or transactions contemplated
herein shall be governed by and interpreted and construed in accordance with the
laws of the State of Colorado, and the State of Colorado shall be the venue for
resolution of all disputes involving this Convertible Debenture.


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         11. AUTHENTICATION. This Convertible Debenture shall be a valid and
binding obligation of the Company upon signature by an officer of the Company,
pursuant to the authorization by resolution of the Board of Directors of the
Company, which is attached hereto as EXHIBIT B, and by reference made a part
hereof.

         In witness whereof the Company has caused this Convertible Debenture to
be signed and issued in its name to Holder this 13th day of September, 2002.

                                              3Si HOLDINGS, INC.,
                                              a Wyoming corporation:

                                              /s/ Frederick J. Slack
                                              ---------------------------------
                                              By: Frederick J. Slack
                                                 ------------------------------
                                              Title: Exec. V.P.
                                                    ---------------------------

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                                    EXHIBIT A

                         SENIOR INDEBTEDNESS OF COMPANY
                       (TO WHICH THIS $100,000 CONVERTIBLE
                            DEBENTURE IS SUBORDINATE)





                          Vectra Bank Colorado National
                                   Association
                            Corporate Private Banking
                          2000 S Colorado Blvd #2-1200
                             Denver, Colorado 80222

                              Loan No: 5094283-9001

                                   $250,000.00



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                                    EXHIBIT B

                          UNANIMOUS CONSENT MINUTES OF
                               BOARD OF DIRECTORS
                              OF 3SI HOLDINGS, INC.

         Pursuant to the provisions of the Wyoming Business Corporation Act, as
amended, the following actions were taken without a meeting of the Board of
Directors of 3SI HOLDINGS, INC. (the "Corporation"), as of September 13, 2002,
by the unanimous written consent of each member of the Board of Directors of the
Corporation.

         RESOLVED, that the Board of Directors of the Corporation hereby
determines that the $100,000 loan to the Corporation from Jerome K. Thorson, who
is an officer and director of the Corporation, such loan to bear interest at a
rate of six and one-half percent (6-1/2%) per annum, for a period of one (1)
year, is in the best interests of the Corporation, and is necessary and
advisable and generally to the advantage and for the benefit of this Corporation
and its stockholders, to allow the Corporation to continue operations and to
expend the necessary up-front costs to perform the Corporation's pending
contract with Wells Fargo Bank, N.A.; and

         FURTHER RESOLVED, that such loan is hereby approved upon the terms and
conditions set forth in the written agreement of Convertible Debenture dated
September 13, 2002 (the "Convertible Debenture"), as submitted to the Board; and

         FURTHER RESOLVED, that the form of Convertible Debenture presented to
the Board be and the same is hereby approved, and the execution of the said
Convertible Debenture by the proper officers of this Corporation is hereby
approved and authorized; and

         FURTHER RESOLVED, that the proper officers, counsel and accountants for
the Corporation be, and they hereby are, authorized and directed to take all
further steps necessary or desirable to implement issuance of the Convertible
Debenture to Jerome K. Thorson, as Holder, in accordance with its terms; and


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         FURTHER RESOLVED, that the proper officers of this Corporation be, and
they hereby are, authorized and directed to execute, in the name and on behalf
of this Corporation and under its corporate seal or otherwise, and to deliver
any and all agreements, certificates, applications or other instruments and to
take from time to time any and all such other action necessary or desirable to
carry out the purposes of the foregoing resolutions.

         IN WITNESS WHEREOF, the undersigned Directors have evidenced their
approval of the above proceedings as of the date first above mentioned.

                                             3SI HOLDING COMPANY, INC.

                                             /s/ Frederick J. Slack
                                             --------------------------------
                                             Frederick J. Slack, Director

                                             /s/ Frank W. Backes
                                             --------------------------------
                                             Frank W. Backes, Director

                                             /s/ F. Larry Valdez
                                             ----------------------------------
                                             F. Larry Valdez, Director

                                             /s/ Jerome K. Thorson
                                             ----------------------------------
                                             Jerome K. Thorson, Director




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