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                                                                     EXHIBIT 4.1

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                      BRL UNIVERSAL EQUIPMENT 2001 A, L.P.
                          BRL UNIVERSAL EQUIPMENT CORP.

                                   as Issuers

                                       and

                              THE BANK OF NEW YORK,

                                   as Trustee


                          FIRST SUPPLEMENTAL INDENTURE

                         Dated as of September 11, 2001


                      8 7/8% Senior Secured Notes due 2008



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         THIS FIRST SUPPLEMENTAL INDENTURE, dated as of September 11, 2001 (this
"First Supplemental Indenture"), is made and entered into by and between BRL
Universal Equipment 2001 A, L.P. ("BRL"), BRL Universal Equipment Corp. ("BRL
Corp." and together with BRL, the "Issuers") and The Bank of New York, as
trustee (the "Trustee"), under an Indenture dated as of February 9, 2001,
between the Issuers, as issuers, and the Trustee, as trustee (the "Original
Indenture"). All capitalized terms used in this First Supplemental Indenture
that are defined in the Original Indenture, either directly or by reference
therein, have the meanings assigned to them therein, except to the extent such
terms are defined in this First Supplemental Indenture or the context clearly
requires otherwise.

         WHEREAS, Section 8.01 of the Original Indenture provides that the
Issuers and the Trustee may amend, waive or supplement the Original Indenture
to, (i) to cure any ambiguity, defect or inconsistency , provided that the same
does not adversely affect the rights of any Holder in any material respect; (ii)
to provide for uncertificated Notes in addition to certificated Notes; (iii) to
comply with any requirements of the Commission in order to effect or maintain
the qualification of the Original Indenture under the TIA; or (iv) to make any
change that would provide any additional benefit or rights to the Holders or
that does not adversely affect the rights of any Holder in any material respect,
without notice to or the consent of any Holder, upon the request of each Issuer
accompanied by a Board Resolution of each Issuer and the documents set forth in
Section 8.06 of the Original Indenture;

         WHEREAS, the Board of Directors of the Issuers have adopted resolutions
authorizing and approving the amendment of Section 1.01 of the Original
Indenture for the purpose of (i) curing any ambiguity, defect or inconsistency
that does not adversely affect the rights of any Holder in any material respect
and (ii) to make changes that do not adversely affect the rights of any Holder
in any material respect, as more particularly described in this First
Supplemental Indenture, and the Issuers and the Trustee are executing and
delivering this First Supplemental Indenture to provide for such amendment;

         WHEREAS, the Trustee has received the items listed in Section 8.06 and
Section 10.04 of the Original Indenture;

         WHEREAS, the Issuers have determined that the amendments described
below do not adversely affect the interests of the Holders in any material
respect;

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties to this First
Supplemental Indenture hereby agree as follows:

                                    ARTICLE I

                        AMENDMENTS TO ORIGINAL INDENTURE

         Section 1.01 Amendments to Section 1.01. Section 1.01 of the Original
Indenture is hereby amended as follows:

         (a) The definition of "Initial Notes" is hereby amended in its entirety
to read as follows:

                  "Initial Notes" means any (i) Notes issued under this
         Indenture for so long as such securities constitute Restricted
         Securities and (ii) any Notes issued under this Indenture that have
         been registered with the Commission pursuant to an effective
         registration statement filed by the Issuer, UCI and UCH and were not
         issued as Exchange Notes."

         (b) The definition of "Unrestricted Global Note" is hereby amended in
its entirety to read as follows:


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                  "Unrestricted Global Note" means a permanent Global Note in
         the form of Exhibit B attached hereto that bears the Global Note Legend
         and that has the "Schedule of Exchanges of Interests in the Global
         Note" attached thereto and that is deposited with or on behalf of and
         registered in the name of the Depositary, representing a series of
         Notes that do not bear the Private Placement Legend."

         (c) The definition of "Registration Rights Agreement" is hereby amended
in its entirety to read as follows:

                  "Registration Rights Agreement" means (i) the Registration
         Rights Agreement dated as of February 9, 2001 among the Issuers, UCI,
         UCH and the Initial Purchasers, as such agreement may be amended,
         supplemented, or modified in accordance with the terms thereof, and
         (ii) any other registration rights agreement in form similar to the
         Registration Rights Agreement defined in clause (i) relating to Initial
         Notes that are not subject to the Registration Rights Agreement defined
         in clause (i), as such agreement may be amended, supplemented, or
         modified in accordance with the terms thereof,."

         (d) The definition of "Issue Date" is hereby amended in its entirety to
read as follows:

                  "Issue Date" means (i) February 9, 2001, with respect to each
         of Section 2.02, the Notes issued on February 9, 2001 and the
         definitions of "BRL Term Loan Agreement," "Equipment Lease Agreement"
         and "Participation Agreement," and (ii) the date of issuance of any
         Notes other than the Notes referred to in (i) herein."

         (e) The definitions of "BRL Term Loan Agreement" and "Limited
Partnership Agreement" are each amended by adding at the end thereof:

                  ",as such agreement may amended, supplemented or modified in
accordance with the terms thereof."

                                   ARTICLE II

                               GENERAL PROVISIONS

         Section 2.01. Ratification of Indenture. The Original Indenture is in
all respects acknowledged, ratified and confirmed, and shall continue in full
force and effect in accordance with the terms thereof and as amended and
supplemented by this First Supplemental Indenture. The Original Indenture and
this First Supplemental Indenture shall be read, taken and construed as one and
the same instrument. All references to the Original Indenture in the Original
Indenture or in any other agreement, document or instrument delivered in
connection therewith or pursuant thereto shall be deemed to refer to the
Original Indenture as amended and supplemented by this First Supplemental
Indenture.

         Section 2.02. Effect of Headings. The Article and Section headings in
this First Supplemental Indenture are for convenience only and shall not affect
the construction of this First Supplemental Indenture.

         Section 2.03. Severability. In case any one or more of the provisions
in this First Supplemental Indenture shall be held invalid, illegal or
unenforceable, in any respect for any reason, the validity, legality and
enforceability of any such provision in every other respect and of the remaining
provisions


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shall not in any way be affected or impaired thereby, it being intended that all
of the provisions hereof shall be enforceable to the full extent permitted by
law.

         Section 2.04. Governing Law. This First Supplemental Indenture and the
Notes shall be governed by and construed in accordance with the law of the State
of New York but without giving effect to applicable principles of conflicts of
law.

         Section 2.05. Counterparts. This First Supplemental Indenture may be
executed in any number of counterparts, each of which so executed shall be
deemed to be an original, but all such counterparts shall together constitute
the same instrument.

         Section 2.06 Trustee Not Responsible for Recitals. The recitals
contained herein shall be taken as statements of the Issuers and the Trustee
assumes no responsibility for their correctness. The Trustee makes no
representations as to the validity or sufficiency of this First Supplemental
Indenture.

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                                   SIGNATURES

         IN WITNESS WHEREOF, the parties to this First Supplemental Indenture
have caused this First Supplemental Indenture to be duly executed and effective
as of September 11, 2001.

                                       BRL UNIVERSAL EQUIPMENT 2001 A, L.P.

                                       BY: BRL UNIVERSAL EQUIPMENT MANAGEMENT,
                                           INC., ITS GENERAL PARTNER


                                       By: /s/ Gregory C. Greene
                                          -----------------------
                                          Gregory C. Greene, President


                                       BRL UNIVERSAL EQUIPMENT CORP.


                                       By: /s/ Gregory C. Greene
                                           ---------------------
                                           Gregory C. Greene, President


                                       THE BANK OF NEW YORK, AS TRUSTEE


                                       By: /s/ Remo J. Reale
                                           -----------------
                                           Remo J. Reale, Vice President




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