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                                                                   EXHIBIT 10.21



                      SUBORDINATED SECURED PROMISSORY NOTE

$142,500                                                        January 27, 1998

        FOR VALUE RECEIVED, JALATE, LTD., a California corporation (herein,
"MAKER"), hereby promises to pay to Katherine U. Sanders (herein, "HOLDER") or
to order the principal sum of One Hundred Forty Two Thousand Five Hundred
Dollars ($142,500), with interest on the unpaid principal balance outstanding
from time to time, computed at a per annum rate of ten percent (10%), commencing
as from the date hereof until January 31, 2000 ("MATURITY DATE"), when all
amounts then remaining unpaid, together with all accrued and unpaid interest
thereon, shall be due and payable. Interest accrued hereon shall be paid on the
last business day of January, April, July and October, commencing April 30,
1998. The principal amount hereof shall be repaid in four (4) equal quarterly
installments, commencing as from April 30, 1999, and continuing until the
Maturity Date when all other amounts then remaining unpaid (principal, interest
and other) shall become due and payable. All payments are to be made in lawful
money of the United States of America to Holder at 3100 Texas Commerce Tower,
Houston, Texas 77002 (c/o Sanders Morris Mundy Inc., Attn: Chris Hoeller) or at
such other place as Holder shall designate in writing to Maker.

        Upon Maker's failure to pay any amount owing hereon as and when due,
such amount due hereunder together with the accrued interest thereon shall to
the extent not in violation of any applicable laws, bear interest at five
percent (5%) per annum in excess of the rate otherwise applicable thereto
("DEFAULT RATE") until such amount is paid, it


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being acknowledged and agreed that the imposition of a higher rate of interest
as herein provided for failure to pay an amount owing hereunder shall not
preclude Holder from accelerating the entire amount due hereunder as a result of
such non-payment, and upon any such acceleration, the amount so accelerated
shall, to the extent not in violation of any applicable laws, bear interest at
the Default Rate until full payment of all such accelerated amounts.

        By acceptance of this Note as evidence of Maker's obligation to repay to
Holder the amounts evidenced hereby, Holder acknowledges and agrees that all
amounts owing hereunder (principal, interest and other) shall be subordinated
and be junior in right of payment to all of Maker's obligations to Heller
Financial, Inc. ("HELLER") and/or Wells Fargo HSBC Trade Bank N.A. ("WELLS
FARGO") relating to present or future loans or other credit accommodations made
to Maker. If an event of default under Maker's loan agreements with either
Heller or Wells Fargo has occurred and is continuing, then Holder shall not be
entitled to and shall not accept any payment from Maker with respect to this
Note unless and until (i) all of Maker's obligations to Heller and/or Wells
Fargo, as applicable, under such agreements have been satisfied in full or (ii)
Heller and/or Wells Fargo, as applicable, consents in writing thereto; provided,
however, that nothing contained herein shall be deemed to prohibit the Secured
Party (defined below) from exercising its rights under the Security and Pledge
Agreement referred to below (including, without limitation, foreclosing upon any
or all of the collateral provided for therein). Further, by acceptance hereof,
Holder hereby waives any and all rights, defenses or protections that may
otherwise be available to him as a surety under



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applicable law, including, without limitation, any right, defense or protection
available to sureties by reason of the Texas Civil Code.

      All persons or corporations now or at any time liable for payment of the
indebtedness evidenced hereby for themselves, their heirs, legal
representatives, successors and assigns, respectively, expressly waive
presentment for payment, demand, notice of dishonor, protest, notice of protest
and diligence in collection, and consent that the time of said payments may be
extended by Holder without in any way modifying, altering, releasing, affecting,
or limiting their respective liability for the indebtedness evidenced hereby.

        If this Note is not paid when due (whether at scheduled maturity, by
acceleration or otherwise), Maker promises to pay all costs of collection
including, without limitation, reasonable attorneys' fees, incurred by Holder,
whether or not suit is filed hereon.

        This Note may be prepaid by Maker, in whole at any time or in part from
time to time, without payment of any premium or penalty on fifteen (15) days
prior notice to Holder of such election to prepay. In addition, Maker agrees to
use the net proceeds of any equity offering to prepay this Note. Maker also
agrees to use a portion of the proceeds of this Note to satisfy in full its
current financial obligations to Air Shop Ltd., a New York corporation ("AIR
SHOP"), pursuant to that certain letter agreement between Maker and Air Shop
dated October 17, 1997, with regard to the acquisition of certain shares of the
capital stock of Air Shop by Maker.

        Maker's obligations under this Note are secured by a Security and Pledge
Agreement between Maker and Secured Party (as therein defined) dated as of even
date


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herewith. The due date of the Note may be accelerated in accordance with the
terms of such Security and Pledge Agreement.

        HOLDER'S RIGHTS UNDER THIS NOTE ARE ALSO SUBJECT TO AN INTERCREDITOR
AGREEMENT DATED AS OF EVEN DATE HEREWITH AND MAY ONLY BE EXERCISED IN ACCORDANCE
THEREWITH.

        No provision of this NOTE is intended to or shall require or permit
Holder, directly or indirectly, to take, collect or receive in money, goods or
any other form, any interest (including amounts deemed by law to be interest) in
excess of the maximum rate of interest permitted by applicable law. If any
amount due from or paid by Maker shall be determined by a court of competent
jurisdiction to be interest in excess of such maximum rate, Maker shall not be
obligated to pay such excess and, if paid, such excess shall be applied against
the unpaid principal balance of this Note or, if and to the extent that this
Note has been paid in full, such excess shall be remitted by Holder to Maker.

      Holder may pursue any rights and remedies as the holder of this Note or
under any security agreement, pledge, guaranty or other collateral documents,
including, without limitation, the Security and Pledge Agreement, independently
or concurrently; provided, however, that only Secured Party may exercise the
rights granted to Secured Party under the Security Agreement; and provided
further that Holder's rights hereunder must be exercised in accordance with and
subject to the conditions set forth in the Intercreditor Agreement. All rights,
remedies or powers herein conferred upon Holder or conferred by the Security and
Pledge Agreement or any other collateral document shall, to the extent not
prohibited by law, be deemed cumulative and not exclusive of any others thereof,
or any other rights, remedies or powers available to Holder. No


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delay or omission of Holder to exercise any right, remedy or power shall impair
the same or be construed to be a waiver of any default or an acquiescence
thereto. No waiver of any default shall extend to or affect any subsequent
default or impair any rights, remedies or powers available to Holder. No single
or partial exercise of any right, remedy or power shall preclude other or future
exercise thereof by Holder.

      This Note has been negotiated in substantial part in the State of Texas
and all questions with respect to the Note and the rights and liabilities of the
parties will be governed by the laws of Texas in all respects, including matters
of construction, validity, enforcement and performance, regardless of the choice
of law provisions of Texas or any other jurisdiction. Any and all disputes
between the parties which may arise pursuant to this Note not resolved by them
will be heard and determined before an appropriate federal or state court
located in Houston, Texas. The parties hereto acknowledge that such courts have
the jurisdiction to interpret and enforce the provisions of this Note and the
parties waive any and all objections that they may have as to personal
jurisdiction or venue in any of the above courts.



                                       JALATE, LTD.,
                                       a California corporation



                                       By: /s/ FREDERICK A. FINDLEY
                                           ------------------------------------
                                           Frederick A. Findley
                                           Vice President and Chief
                                           Financial Officer


Accepted:


________________________
Katherine U. Sanders



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all objections that they may have as to personal jurisdiction or venue in any
of the above courts.


                                    JALATE, LTD.
                                    a California corporation


                                    By:
                                       -----------------------------------
                                          Frederick A. Findley
                                          Vice President and Chief
                                          Financial Officer



Accepted:

/s/ KATHERINE U. SANDERS
-----------------------------------
Katherine U. Sanders




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