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                                  Exhibit 10.36

                                                                       EXECUTION
                                                                     COUNTERPART



                               SECURITY AGREEMENT


         1. GRANT OF SECURITY INTEREST. For valuable consideration, the
undersigned AIRCOMP L.L.C., a Delaware limited liability company ("Debtor"),
hereby grants and transfers to WELLS FARGO BANK TEXAS, NATIONAL ASSOCIATION
individually and as Collateral Agent for itself and other lenders from time to
time and as Collateral Agent for Wells Fargo Bank, National Association
(individually and collectively "Bank") a security interest in all of the
property of Debtor described as follows (collectively, the "Collateral"):

         (a) all accounts, deposit accounts, contract rights, chattel paper
(whether electronic or tangible), instruments, promissory notes, documents,
general intangibles, payment intangibles, software, letter of credit rights,
health-care insurance receivables and other rights to payment of every kind now
existing or at any time hereafter arising;

         (b) all inventory, goods held for sale or lease or to be furnished
under contracts for service, or goods so leased or furnished, raw materials,
component parts, work in process and other materials used or consumed in
Debtor's business, now or at any time hereafter owned or acquired by Debtor,
wherever located, and all products thereof, whether in the possession of Debtor,
any warehousemen, any bailee or any other person, or in process of delivery, and
whether located at Debtor's places of business or elsewhere;

         (c) all warehouse receipts, bills of sale, bills of lading and other
documents of every kind (whether or not negotiable) in which Debtor now has or
at any time hereafter acquires any interest, and all additions and accessions
thereto, whether in the possession or custody of Debtor, any bailee or any other
person for any purpose;

         (d) all money and property heretofore, now or hereafter delivered to or
deposited with Bank or otherwise coming into the possession, custody or control
of Bank (or any agent or bailee of Bank) in any manner or for any purpose
whatsoever during the existence of this Agreement and whether held in a general
or special account or deposit for safekeeping or otherwise;

         (e) all right, title and interest of Debtor under licenses, guaranties,
warranties, management agreements, marketing or sales agreements, escrow
contracts, indemnity agreements, insurance policies, service or maintenance
agreements, supporting obligations and other similar contracts of every kind in
which Debtor now has or at any time hereafter shall have an interest;

         (f) all goods, tools, machinery, furnishings, furniture and other
equipment and fixtures of every kind now existing or hereafter acquired, and all
improvements, replacements, accessions and additions thereto and embedded
software included therein, whether located on any property owned or leased by
Debtor or elsewhere, including without limitation, any of the foregoing now or
at any time hereafter located at or installed on the land or in the improvements
at any of the real property owned or leased by Debtor, and all such goods after
they have been severed and removed from any of said real property; and

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         (g) all motor vehicles, trailers, mobile homes, manufactured homes,
boats, other rolling stock and related equipment of every kind now existing or
hereafter acquired and all additions and accessories thereto, whether located on
any property owned or leased by Debtor or elsewhere; together with whatever is
receivable or received when any of the foregoing or the proceeds thereof are
sold, leased, collected, exchanged or otherwise disposed of, whether such
disposition is voluntary or involuntary, including without limitation, all
rights to payment, including returned premiums, with respect to any insurance
relating to any of the foregoing, and all rights to payment with respect to any
claim or cause of action affecting or relating to any of the foregoing
(collectively, "Proceeds").

         2. OBLIGATIONS SECURED. The obligations secured hereby are the payment
and performance of: (a) all present and future Indebtedness, as defined in the
Credit Agreement executed on even date herewith to be the Line of Credit, Term
Loan, Delayed Draw Term Loan, and Wells Fargo Commercial MasterCard Agreement,
of Debtor to Bank; (b) all obligations of Debtor and rights of Bank under this
Agreement; and (c) all present and future obligations of Debtor to Bank of other
kinds. The word "Indebtedness" is used herein in its most comprehensive sense
and includes any and all advances, debts, obligations and liabilities of Debtor,
or any of them, heretofore, now or hereafter made, incurred or created, whether
voluntary or involuntary and however arising, whether due or not due, absolute
or contingent, liquidated or unliquidated, determined or undetermined, secured
or unsecured and whether Debtor may be liable individually or jointly with
others, or whether recovery upon such Indebtedness may be or hereafter becomes
unenforceable and shall include, without limitation: (i) all indebtedness and
obligations of Debtor owing to Wells Fargo Bank, National Association arising
under any Wells Fargo Corporate Card agreement, Wells Fargo Bank Commercial
MasterCard Customer Agreement and any document executed or referred to therein
together with any and all amendments, modifications, and replacements thereof,
and (ii) all Indebtedness (as defined in that certain Credit Agreement of even
date herewith between Debtor and Wells Fargo Bank Texas, National Association
(the "Credit Agreement")).

         3. TERMINATION. This Agreement will terminate upon the performance of
all obligations of Debtor to Bank, including without limitation, the payment of
all Indebtedness of Debtor to Bank, and the termination of all commitments of
Bank to extend credit to Debtor, existing at the time Bank receives written
notice from Debtor of the termination of this Agreement.

         4. OBLIGATIONS OF BANK. Bank has no obligation to make any loans
hereunder. Any money received by Bank in respect of the Collateral may be
deposited, at Bank's option, into a non-interest bearing account over which
Debtor shall have no control, and the same shall, for all purposes, be deemed
Collateral hereunder.

         5. REPRESENTATIONS AND WARRANTIES. Debtor represents and warrants to
Bank that: (a) Debtor's legal name is exactly as set forth on the first page of
this Agreement, and all of Debtor's organizational documents or agreements
delivered to Bank are complete and accurate in every respect; (b) Debtor is the
owner and has possession or control of the Collateral and Proceeds; (c) Debtor
has the exclusive right to grant a security interest in the Collateral and


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Proceeds; (d) all Collateral and Proceeds are genuine, free from liens, adverse
claims, setoffs, default, prepayment, defenses and conditions precedent of any
kind or character, except the lien created hereby or as otherwise agreed to by
Bank, or as heretofore disclosed by Debtor to Bank, in writing; (e) all
statements contained herein and, where applicable, in the Collateral are true
and complete in all material respects; (f) no financing statement covering any
of the Collateral or Proceeds, and naming any secured party other than Bank, is
on file in any public office; (g) where Collateral consists of rights to
payment, all persons appearing to be obligated on the Collateral and Proceeds
have authority and capacity to contract and are bound as they appear to be, all
property subject to chattel paper has been properly registered and filed in
compliance with law and to perfect the interest of Debtor in such property, and
all such Collateral and Proceeds comply with all applicable laws concerning
form, content and manner of preparation and execution, including where
applicable Federal Reserve Regulation Z and any State consumer credit laws; and
(h) where the Collateral consists of equipment, Debtor is not in the business of
selling goods of the kind included within such Collateral, and Debtor
acknowledges that no sale or other disposition of any such Collateral, including
without limitation, any such Collateral which Debtor may deem to be surplus, has
been consented to or acquiesced in by Bank, except as specifically set forth in
writing by Bank.

         6. COVENANTS OF DEBTOR.

         (a) Debtor agrees in general: (i) to pay Indebtedness secured hereby
when due; (ii) to indemnify Bank against all losses, claims, demands,
liabilities and expenses of every kind caused by property subject hereto; (iii)
to pay all costs and expenses, including reasonable attorneys' fees, incurred by
Bank in the perfection and preservation of the Collateral or Bank's interest
therein and/or the realization, enforcement and exercise of Bank's rights,
powers and remedies hereunder; (iv) to permit Bank to exercise its powers; (v)
to execute and deliver such documents as Bank deems necessary to create, perfect
and continue the security interests contemplated hereby; (vi) not to change its
name, and as applicable, its chief executive office, its principal residence or
the jurisdiction in which it is organized and/or registered without giving Bank
prior written notice thereof; (vii) not to change the places where Debtor keeps
any Collateral or Debtor's records concerning the Collateral and Proceeds
without giving Bank prior written notice of the address to which Debtor is
moving same; and (viii) to cooperate with Bank in perfecting all security
interests granted herein and in obtaining such agreements from third parties as
Bank deems necessary, proper or convenient in connection with the preservation,
perfection or enforcement of any of its rights hereunder.

         (b) Debtor agrees with regard to the Collateral and Proceeds, unless
Bank agrees otherwise in writing: (i) that Bank is authorized to file financing
statements in the name of Debtor to perfect Bank's security interest in
Collateral and Proceeds; (ii) where applicable, to insure the Collateral with
Bank named as loss payee, in form, substance and amounts, under agreements,
against risks and liabilities, and with insurance companies satisfactory to
Bank; (iii) where applicable, to operate the Collateral in accordance with all
applicable statutes, rules and regulations relating to the use and control
thereof, and not to use any Collateral for any unlawful purpose or in any way
that would void any insurance required to be carried in connection therewith;
(iv) not to remove the Collateral from Debtor's premises, except (A) for
deliveries to buyers in the ordinary course of Debtor's business and (B)


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Collateral which consists of mobile goods as defined in the Texas Business and
Commerce Code, in which case Debtor agrees not to remove or permit the removal
of such Collateral from its state of domicile or states where it is qualified to
do business for a period in excess of thirty (30) calendar days unless pursuant
to a written agreement; (v) to pay when due all license fees, registration fees
and other charges in connection with any Collateral; (vi) not to permit any lien
on the Collateral or Proceeds, including without limitation, liens arising from
repairs to or storage of the Collateral, except in favor of Bank; (vii) not to
sell, hypothecate or dispose of, nor permit the transfer by operation of law of,
any of the Collateral or Proceeds or any interest therein, except sales of
inventory to buyers in the ordinary course of Debtor's business; (viii) to
permit Bank to inspect the Collateral at any time; (ix) to keep, in accordance
with generally accepted accounting principles, complete and accurate records
regarding all Collateral and Proceeds, and to permit Bank to inspect the same
and make copies thereof at any reasonable time; (x) if requested by Bank, to
receive and use reasonable diligence to collect Collateral consisting of
accounts and other rights to payment and Proceeds, in trust and as the property
of Bank, and to immediately endorse as appropriate and deliver such Collateral
and Proceeds to Bank daily in the exact form in which they are received together
with a collection report in form satisfactory to Bank; (xi) not to commingle
Collateral or Proceeds, or collections thereunder, with other property; (xii) to
give only normal allowances and credits and to advise Bank thereof immediately
in writing if they affect any rights to payment or Proceeds in any material
respect; (xiii) from time to time, when requested by Bank, to prepare and
deliver a schedule of all Collateral and Proceeds subject to this Agreement and
to assign in writing and deliver to Bank all accounts, contracts, leases and
other chattel paper, instruments, documents and other evidences thereof; (xiv)
in the event Bank elects to receive payments of rights to payment or Proceeds
hereunder, to pay all expenses incurred by Bank in connection therewith,
including expenses of accounting, correspondence, collection efforts, reporting
to account or contract debtors, filing, recording, record keeping and expenses
incidental thereto; and (xv) to provide any service and do any other acts which
may be necessary to maintain, preserve and protect all Collateral and, as
appropriate and applicable, to keep all Collateral in good and saleable
condition, to deal with the Collateral in accordance with the standards and
practices adhered to generally by users and manufacturers of like property, and
to keep all Collateral and Proceeds free and clear of all defenses, rights of
offset and counterclaims.

         7. POWERS OF BANK. Debtor appoints Bank its true attorney in fact to
perform any of the following powers, which are coupled with an interest, are
irrevocable until termination of this Agreement and may be exercised from time
to time by Bank's officers and employees, or any of them, whether or not Debtor
is in default: (a) to give notice to account debtors or others of Bank's rights
in the Collateral and Proceeds, to enforce or forebear from enforcing the same
and make extension and modification agreements with respect thereto; (b) to
release persons liable on Collateral or Proceeds and to give receipts and
acquittances and compromise disputes in connection therewith; (c) to release or
substitute security; (d) to resort to security in any order; (e) to prepare,
execute, file, record or deliver notes, assignments, schedules, designation
statements, financing statements, continuation statements, termination
statements, statements of assignment, applications for registration or like
papers to perfect, preserve or release Bank's interest in the Collateral and
Proceeds; (f) to receive, open and read mail addressed to Debtor; (g) to take
cash, instruments for the payment of money and other property to which Bank is


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entitled; (h) to verify facts concerning the Collateral and Proceeds by inquiry
of obligors thereon, or otherwise, in its own name or a fictitious name; (i) to
endorse, collect, deliver and receive payment under instruments for the payment
of money constituting or relating to Proceeds; (j) to prepare, adjust, execute,
deliver and receive payment under insurance claims, and to collect and receive
payment of and endorse any instrument in payment of loss or returned premiums or
any other insurance refund or return, and to apply such amounts received by
Bank, at Bank's sole option, toward repayment of the Indebtedness or, where
appropriate, replacement of the Collateral; (k) to exercise all rights, powers
and remedies which Debtor would have, but for this Agreement, with respect to
all Collateral and Proceeds subject hereto; (l) to enter onto Debtor's premises
in inspecting the Collateral; (m) to make withdrawals from and to close deposit
accounts or other accounts with any financial institution, wherever located,
into which Proceeds may have been deposited, and to apply funds so withdrawn to
payment of the Indebtedness; (n) to preserve or release the interest evidenced
by chattel paper to which Bank is entitled hereunder and to endorse and deliver
any evidence of title incidental thereto; (o) to do all acts and things and
execute all documents in the name of Debtor or otherwise, deemed by Bank as
necessary, proper and convenient in connection with the preservation, perfection
or enforcement of its rights hereunder that Bank, in its sole discretion, needs
to do immediately; and (p) to perform any other obligation of Debtor hereunder
in Debtor's name or otherwise with thirty (30) days written notice to Debtor.

         8. PAYMENT OF PREMIUMS, TAXES, CHARGES, LIENS AND ASSESSMENTS. Debtor
agrees to pay, prior to delinquency, all insurance premiums, taxes, charges,
liens and assessments against the Collateral and Proceeds, and upon the failure
of Debtor to do so, Bank at its option may pay any of them and shall be the sole
judge of the legality or validity thereof and the amount necessary to discharge
the same. Any such payments made by Bank shall be obligations of Debtor to Bank,
due and payable immediately upon demand, together with interest at a rate
determined in accordance with the provisions of this Agreement, and shall be
secured by the Collateral and Proceeds, subject to all terms and conditions of
this Agreement.

         9. EVENTS OF DEFAULT. The occurrence of any of the following shall
constitute an "Event of Default" under this Agreement: (a) any default in the
payment or performance of any obligation, or any defined event of default, under
(i) any contract or instrument evidencing any Indebtedness, or (ii) any other
agreement between Debtor and Bank, including without limitation any loan
agreement, relating to or executed in connection with any Indebtedness; (b) any
representation or warranty made by Debtor herein shall prove to be incorrect,
false or misleading in any material respect when made; (c) Debtor shall fail to
observe or perform any obligation or agreement contained herein; (d) any
impairment of the rights of Bank in any Collateral or Proceeds, or any
attachment or like levy on any property of Debtor; and (e) Bank, in good faith,
believes any or all of the Collateral and/or Proceeds to be in danger of misuse,
dissipation, commingling, loss, theft, damage or destruction, or otherwise in
jeopardy or unsatisfactory in character or value.

         10. REMEDIES. Upon the occurrence of any Event of Default, Bank shall
have the right to declare immediately due and payable all or any Indebtedness
secured hereby and to terminate any commitments to make loans or otherwise
extend credit to Debtor. Bank shall have all other rights, powers, privileges
and remedies granted to a secured party upon default under the Texas Business
and Commerce Code or otherwise provided by law, including without limitation,
the right (a) to contact all persons obligated to Debtor on any Collateral or
Proceeds and to instruct such persons to deliver all Collateral and/or Proceeds


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directly to Bank, and (b) to sell, lease, license or otherwise dispose of any or
all Collateral. All rights, powers, privileges and remedies of Bank shall be
cumulative. No delay, failure or discontinuance of Bank in exercising any right,
power, privilege or remedy hereunder shall affect or operate as a waiver of such
right, power, privilege or remedy; nor shall any single or partial exercise of
any such right, power, privilege or remedy preclude, waive or otherwise affect
any other or further exercise thereof or the exercise of any other right, power,
privilege or remedy. Any waiver, permit, consent or approval of any kind by Bank
of any default hereunder, or any such waiver of any provisions or conditions
hereof, must be in writing and shall be effective only to the extent set forth
in writing. It is agreed that public or private sales or other dispositions, for
cash or on credit, to a wholesaler or retailer or investor, or user of property
of the types subject to this Agreement, or public auctions, are all commercially
reasonable since differences in the prices generally realized in the different
kinds of dispositions are ordinarily offset by the differences in the costs and
credit risks of such dispositions. While an Event of Default exists: (a) Debtor
will deliver to Bank from time to time, as requested by Bank, current lists of
all Collateral and Proceeds; (b) Debtor will not dispose of any Collateral or
Proceeds except on terms approved by Bank; (c) at Bank's request, Debtor will
assemble and deliver all Collateral and Proceeds, and books and records
pertaining thereto, to Bank at a reasonably convenient place designated by Bank;
and (d) Bank may, without notice to Debtor, enter onto Debtor's premises and
take possession of the Collateral. With respect to any sale or other disposition
by Bank of any Collateral subject to this Agreement, Debtor hereby expressly
grants to Bank the right to sell such Collateral using any or all of Debtor's
trademarks, trade names, trade name rights and/or proprietary labels or marks.
Debtor further agrees that Bank shall have no obligation to process or prepare
any Collateral for sale or other disposition.

         11. DISPOSITION OF COLLATERAL AND PROCEEDS; TRANSFER OF INDEBTEDNESS.
In disposing of Collateral hereunder, Bank may disclaim all warranties of title,
possession, quiet enjoyment and the like. Any proceeds of any disposition of any
Collateral or Proceeds, or any part thereof, shall be applied: first by Wells
Fargo Bank Texas, National Association to the payment of expenses incurred by
Wells Fargo Bank Texas, National Association in connection with the foregoing,
including reasonable attorneys' fees; second, such proceeds shall be applied by
Wells Fargo Bank Texas, National Association toward the payment of the
Indebtedness owing to Wells Fargo Bank Texas, National Association and the other
lenders who are parties to the Credit Agreement, if any, in such order of
application as Wells Fargo Bank Texas, National Association may from time to
time elect; third, such proceeds shall be applied to the payment of expenses
incurred by Wells Fargo Bank, National Association in connection with the
foregoing, including reasonable attorneys' fees; fourth, such proceeds shall be
applied to the payment of the Indebtedness owing to Wells Fargo Bank, National
Association in such order of application as Wells Fargo Bank, National
Association may from time to time elect; and fifth, the balance of such proceeds
shall be given to Debtor if, and only if, all Indebtedness and obligations to
the Bank have been fully and finally paid. Upon the transfer of all or any part
of the Indebtedness, Bank may transfer all or any part of the Collateral or
Proceeds and shall be fully discharged thereafter from all liability and
responsibility with respect to any of the foregoing so transferred, and the
transferee shall be vested with all rights and powers of Bank hereunder with
respect to any of the foregoing so transferred; but with respect to any
Collateral or Proceeds not so transferred, Bank shall retain all rights, powers,
privileges and remedies herein given.

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         12. STATUTE OF LIMITATIONS. Until all Indebtedness shall have been paid
in full and all commitments by Bank to extend credit to Debtor have been
terminated, the power of sale or other disposition and all other rights, powers,
privileges and remedies granted to Bank hereunder shall continue to exist and
may be exercised by Bank at any time and from time to time irrespective of the
fact that the Indebtedness or any part thereof may have become barred by any
statute of limitations, or that the personal liability of Debtor may have
ceased, unless such liability shall have ceased due to the payment in full of
all Indebtedness secured hereunder.

         13. MISCELLANEOUS. When there is more than one Debtor named herein: (a)
the word "Debtor" shall mean all or any one or more of them as the context
requires; (b) the obligations of each Debtor hereunder are joint and several;
and (c) until all Indebtedness shall have been paid in full, no Debtor shall
have any right of subrogation or contribution, and each Debtor hereby waives any
benefit of or right to participate in any of the Collateral or Proceeds or any
other security now or hereafter held by Bank. Debtor hereby waives any right to
require Bank to (i) proceed against Debtor or any other person, (ii) proceed
against or exhaust any security from Debtor or any other person, (iii) perform
any obligation of Debtor with respect to any Collateral or Proceeds, and (d)
make any presentment or demand, or give any notices of any kind, including
without limitation, any notice of nonpayment or nonperformance, protest, notice
of protest, notice of dishonor, notice of intention to accelerate or notice of
acceleration hereunder or in connection with any Collateral or Proceeds. Debtor
further waives any right to direct the application of payments or security for
any indebtedness of Debtor or indebtedness of customers of Debtor. Any
requirement of reasonable notice to Debtor with respect to the sale or other
disposition of Collateral shall be met if such notice is given pursuant to the
requirements of Section 14 hereof at least 5 days before the date of any public
disposition or the date after which any private sale or other disposition will
be made.

         14. NOTICES. All notices, requests and demands required under this
Agreement must be in writing, addressed to Bank at the address specified in any
other loan documents entered into between Debtor and Bank and to Debtor at the
address of its chief executive office (or principal residence, if applicable)
specified below or to such other address as any party may designate by written
notice to each other party, and shall be deemed to have been given or made as
follows: (a) if personally delivered, upon delivery; (b) if sent by mail, upon
the earlier of the date of receipt or three (3) days after deposit in the U.S.
mail, first class and postage prepaid; and (c) if sent by telecopy, upon
receipt.

         15. COSTS, EXPENSES AND ATTORNEYS' FEES. Debtor shall pay to Bank
immediately upon demand the full amount of all payments, advances, charges,
costs and expenses, including reasonable attorneys' fees (to include outside
counsel fees and all allocated costs of Bank's in-house counsel to the extent
permissible), incurred by Bank in exercising any right, power, privilege or
remedy conferred by this Agreement or in the enforcement thereof, whether
incurred at the trial or appellate level, in an arbitration proceeding or
otherwise, and including any of the foregoing incurred in connection with any
bankruptcy proceeding (including without limitation, any adversary proceeding,
contested matter or motion brought by Bank or any other person) relating to
Debtor or in any way affecting any of the Collateral or Bank's ability to
exercise any of its rights or remedies with respect thereto. All of the
foregoing shall be paid by Debtor from the date of demand to the date paid in
full with interest at the maximum rate permitted by applicable law.

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         16. SUCCESSORS; ASSIGNS; AMENDMENT. This Agreement shall be binding
upon and inure to the benefit of the heirs, executors, administrators, legal
representatives, successors and assigns of the parties, and may be amended or
modified only in writing signed by Bank and Debtor.

         17. SEVERABILITY OF PROVISIONS. If any provision of this Agreement
shall be held to be prohibited by or invalid under applicable law, such
provision shall be ineffective only to the extent of such prohibition or
invalidity, without invalidating the remainder of such provision or any
remaining provisions of this Agreement.

         18. GOVERNING LAW. This Agreement shall be governed by and construed in
accordance with the laws of the State of Texas.

         19. STATE OF ORGANIZATION. Debtor warrants that Debtor is an
organization formed under the laws of the State of Delaware.

         20. LOCATION OF CHIEF EXECUTIVE OFFICE. Debtor warrants that its chief
executive office (or principal residence, if applicable) is located at the
following address: 7660 Woodway, Suite 200, Houston, Texas 77063.

         21. LOCATION OF COLLATERAL. Debtor warrants that the Collateral (except
goods in transit) is located or domiciled at the following additional addresses:

         (a) 702 Railroad Avenue, Ft. Stockton, Texas 79735

         (b) 705 Railroad Avenue, Ft. Stockton, Texas 79735

         (c) 2896 I-70 Business Loop, Grand Junction, Colorado 81505

         (d) 37 South University Street, Healdsburg, California 95488

         (e) 1910 Rustic Place, Farmington, New Mexico 87401

         (f) 7660 Woodway, Suite 200, Houston, Texas 77063

         22. SUBORDINATION. THE PARTIES HERETO AGREE THAT ANY AND ALL
INDEBTEDNESS, OBLIGATIONS, AND LIENS IN FAVOR OF WELLS FARGO BANK TEXAS,
NATIONAL ASSOCIATION OF DEBTOR AND ANY OTHER LENDERS WHO MAY FROM TIME TO TIME
BECOME A PARTY TO THE CREDIT AGREEMENT, SHALL BE SENIOR AND SUPERIOR TO ALL
INDEBTEDNESS, OBLIGATIONS AND LIENS CREDITED IN FAVOR OF WELLS FARGO BANK TEXAS,
NATIONAL ASSOCIATION, WHICH SHALL BE SUBORDINATE AND INFERIOR AS TO BOTH DEBT
AND LIENS TO WELLS FARGO BANK TEXAS, NATIONAL ASSOCIATION IN ALL RESPECTS.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

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         IN WITNESS WHEREOF, this Agreement has been duly executed as of June
27, 2003.

                                    AIRCOMP L.L.C., a limited liability company


                                    By:  /s/ Terry Keane

                                    Name:    Terry Keane


                                    Title:   President



                                    WELLS FARGO BANK TEXAS, NATIONAL
                                    ASSOCIATION, Individually and as
                                    Collateral Agent


                                    By:  /s/ Alan Smith


                                    Name:  Alan Smith


                                    Title:  Vice President



                                    WELLS FARGO BANK TEXAS,
                                    NATIONAL ASSOCIATION


                                    By:  /s/ Alan Smith

                                    Name:/s/ Alan Smith

                                    Title:Vice President


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                                                     WELLS FARGO BANK,
                                                     NATIONAL ASSOCIATION


                                                     By: /s/ Alan Smith

                                                     Name:Alan Smith

                                                     Title:Vice President





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