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                                                                    EXHIBIT 4.21

                             SUPPLEMENTAL INDENTURE

                  SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated
as of October 22, 2003, among Creation Group Holdings, Inc., an Indiana
corporation, Creation Group, Inc., an Indiana corporation (each a "Guaranteeing
Subsidiary" and together the "Guaranteeing Subsidiaries"), which are
subsidiaries of Dura Operating Corp. (or its permitted successor), a Delaware
corporation (the "Company"), the Company, the other Guarantors (as defined in
the Indenture referred to herein) and BNY Midwest Trust Company, as trustee
under the indenture referred to below (the "Trustee").

                               W I T N E S S E T H

                  WHEREAS, the Company has heretofore executed and delivered to
the Trustee an indenture (the "Indenture"), dated as of April 18, 2002,
providing for the issuance of an aggregate principal amount of $350.0 million of
85/8% Senior Notes due 2012 (the "Notes");

                  WHEREAS, the Indenture provides that under certain
circumstances each Guaranteeing Subsidiary shall execute and deliver to the
Trustee a supplemental indenture pursuant to which such Guaranteeing Subsidiary
shall unconditionally guarantee all of the Company's Obligations under the Notes
and the Indenture on the terms and conditions set forth herein (each a
"Subsidiary Guarantee" and together the "Subsidiary Guarantees"); and

                  WHEREAS, pursuant to Section 9.06 of the Indenture, the
Trustee is authorized to execute and deliver this Supplemental Indenture.

                  NOW THEREFORE, in consideration of the foregoing and for other
good and valuable consideration, the receipt of which is hereby acknowledged,
each Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

                  1. CAPITALIZED TERMS. Capitalized terms used herein without
definition shall have the meanings assigned to them in the Indenture.

                  2. AGREEMENT TO GUARANTEE. Each Guaranteeing Subsidiary hereby
agrees as follows:

                  (a)      Along with all Guarantors named in the Indenture, to
jointly and severally guarantee to each Holder of a Note authenticated and
delivered by the Trustee and to the Trustee and its successors and assigns, the
Notes or the obligations of the Company hereunder or thereunder, that:

                           (i)      the principal of and interest on the Notes
                                    will be promptly paid in full when due,
                                    whether at maturity, by acceleration,
                                    redemption or otherwise, and interest on the
                                    overdue

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                                    principal of and interest on the Notes, if
                                    any, if lawful, and all other obligations of
                                    the Company to the Holders or the Trustee
                                    hereunder or thereunder will be promptly
                                    paid in full or performed, all in accordance
                                    with the terms hereof and thereof; and

                           (ii)     in case of any extension of time of payment
                                    or renewal of any Notes or any of such other
                                    obligations, that same will be promptly paid
                                    in full when due or performed in accordance
                                    with the terms of the extension or renewal,
                                    whether at stated maturity, by acceleration
                                    or otherwise. Failing payment when due of
                                    any amount so guaranteed or any performance
                                    so guaranteed for whatever reason, the
                                    Guarantors shall be jointly and severally
                                    obligated to pay the same immediately.

                  (b)      The obligations hereunder shall be unconditional,
irrespective of the validity, regularity or enforceability of the Notes or the
Indenture, the absence of any action to enforce the same, any waiver or consent
by any Holder of the Notes with respect to any provisions hereof or thereof, the
recovery of any judgment against the Company, any action to enforce the same or
any other circumstance which might otherwise constitute a legal or equitable
discharge or defense of a guarantor.

                  (c)      The following is hereby waived: diligence,
presentment, demand of payment, filing of claims with a court in the event of
insolvency or bankruptcy of the Company, any right to require a proceeding first
against the Company, protest, notice and all demands whatsoever.

                  (d)      This Subsidiary Guarantee shall not be discharged
except by complete performance of the obligations contained in the Notes and the
Indenture.

                  (e)      If any Holder or the Trustee is required by any court
or otherwise to return to the Company, the Guarantors, or any Custodian,
trustee, liquidator or other similar official acting in relation to either the
Company or the Guarantors, any amount paid by either to the Trustee or such
Holder, this Subsidiary Guarantee, to the extent theretofore discharged, shall
be reinstated in full force and effect.

                  (f)      The Guaranteeing Subsidiary shall not be entitled to
any right of subrogation in relation to the Holders in respect of any
obligations guaranteed hereby until payment in full of all obligations
guaranteed hereby.

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                  (g)      As between the Guarantors, on the one hand, and the
Holders and the Trustee, on the other hand, (x) the maturity of the obligations
guaranteed hereby may be accelerated as provided in Article 6 of the Indenture
for the purposes of this Subsidiary Guarantee, notwithstanding any stay,
injunction or other prohibition preventing such acceleration in respect of the
obligations guaranteed hereby, and (y) in the event of any declaration of
acceleration of such obligations as provided in Article 6 of the Indenture, such
obligations (whether or not due and payable) shall forthwith become due and
payable by the Guarantors for the purpose of this Subsidiary Guarantee.

                  (h)      The Guarantors shall have the right to seek
contribution from any non-paying Guarantor so long as the exercise of such right
does not impair the rights of the Holders under the Guarantee.

                  (i)      Pursuant to Section 10.03 of the Indenture, after
giving effect to any maximum amount and any other contingent and fixed
liabilities that are relevant under any applicable Bankruptcy or fraudulent
conveyance laws, and after giving effect to any collections from, rights to
receive contribution from or payments made by or on behalf of any other
Guarantor in respect of the obligations of such other Guarantor under Article 10
of the Indenture shall result in the obligations of such Guarantor under its
Subsidiary Guarantee not constituting a fraudulent transfer or conveyance.

                  3. EXECUTION AND DELIVERY. Each Guaranteeing Subsidiary agrees
that the Subsidiary Guarantees shall remain in full force and effect
notwithstanding any failure to endorse on each Note a notation of such
Subsidiary Guarantee.

                  4. GUARANTEEING SUBSIDIARIES MAY CONSOLIDATE, ETC. ON CERTAIN
TERMS.

                  (a)      The Guaranteeing Subsidiaries may not sell or
                           otherwise dispose of all or substantially all of
                           their assets to, or consolidate with or merge with or
                           into (whether or not such Guaranteeing Subsidiary is
                           the surviving Person) another Person unless:

                           (i)      immediately after giving effect to such
                                    transaction, no Default or Event of Default
                                    exists; and

                           (ii)     either:

                                    (A)      the Person acquiring the property
                                             in any such sale or disposition or
                                             the Person formed by or surviving
                                             any such consolidation or merger
                                             assumes all the obligations of such
                                             Guaranteeing Subsidiary under

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                                             the Indenture, the Guaranty and the
                                             Registration Rights Agreement,
                                             pursuant to a supplemental
                                             indenture satisfactory to the
                                             Trustee and appropriate collateral
                                             documents satisfactory to the
                                             Trustee; or

                                    (B)      the Net Proceeds of such sale or
                                             other disposition are applied in
                                             accordance with the applicable
                                             provisions of the Indenture.

                  (b)      In case of any such consolidation, merger, sale or
                           conveyance and upon the assumption by the successor
                           Person, by supplemental indenture, executed and
                           delivered to the Trustee and satisfactory in form to
                           the Trustee, of the Subsidiary Guarantees endorsed
                           upon the Notes and the due and punctual performance
                           of all of the covenants and conditions of the
                           Indenture to be performed by the Guarantor, such
                           successor corporation shall succeed to and be
                           substituted for the Guarantor with the same effect as
                           if it had been named herein as a Guarantor. Such
                           successor corporation thereupon may cause to be
                           signed any or all of the Subsidiary Guarantees to be
                           endorsed upon all of the Notes issuable hereunder
                           which theretofore shall not have been signed by the
                           Company and delivered to the Trustee. All the
                           Subsidiary Guarantees so issued shall in all respects
                           have the same legal rank and benefit under the
                           Indenture as the Subsidiary Guarantees theretofore
                           and thereafter issued in accordance with the terms of
                           the Indenture as though all of such Subsidiary
                           Guarantees had been issued at the date of the
                           execution hereof.

                  (c)      Except as set forth in Articles 4 and 5 of the
                           Indenture, and notwithstanding clauses (a) and (b)
                           above, nothing contained in the Indenture or in any
                           of the Notes shall prevent any consolidation or
                           merger of a Guarantor with or into the Company or
                           another Guarantor, or shall prevent any sale or
                           conveyance of the property of a Guarantor as an
                           entirety or substantially as an entirety to the
                           Company or another Guarantor.

                  5. RELEASES.

                  (a)      The Subsidiary Guarantee of a Guarantor will be
                           released (i) in connection with any sale or other
                           disposition of all or substantially all of the assets
                           of that Guarantor (including by way of merger or
                           consolidation), to a Person that is not (either
                           before or after giving effect to such

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                           transaction) a Restricted Subsidiary of the Company,
                           if the Guarantor applies the Net Proceeds of that
                           sale or other disposition in accordance with Section
                           4.10 of the Indenture; (ii) in connection with any
                           sale of all of the capital stock of a Guarantor to a
                           person that is not (either before or after giving
                           effect to such transaction) a Restricted Subsidiary
                           of the Company, if the Company applies the Net
                           Proceeds of that sale in accordance with Section 4.10
                           of the Indenture; (iii) if the Company properly
                           designates any Restricted Subsidiary that is a
                           Guarantor as an Unrestricted Subsidiary; (iv) if that
                           Guarantor ceases to guarantee, pledge any of its
                           assets or otherwise provide direct or indirect credit
                           support for any Indebtedness or other obligations of
                           Dura Automotive Systems, Inc., the Company or any
                           Restricted Subsidiary; or (v) in connection with the
                           sale, disposition or transfer of all of the assets of
                           a Guarantor to another Guarantor or the Company. Upon
                           delivery by the Company to the Trustee of an
                           Officers' Certificate and an Opinion of Counsel to
                           the effect that such sale or other disposition was
                           made by the, Company in accordance with the
                           provisions of the Indenture, including without
                           limitation Section 4.10 of the Indenture, the Trustee
                           shall execute any documents reasonably required in
                           order to evidence the release of any Guarantor from
                           its obligations under its Subsidiary Guarantee.

                  (b)      Any Guarantor not released from its obligations under
                           its Subsidiary Guarantee shall remain liable for the
                           full amount of principal of and interest on the Notes
                           and for the other obligations of any Guarantor under
                           the Indenture as provided in Article 10 of the
                           Indenture.

                  6. NO RECOURSE AGAINST OTHERS. No past, present or future
director, officer, employee, incorporator, stockholder or agent of the
Guaranteeing Subsidiaries, as such, shall have any liability for any obligations
of the Company or any Guaranteeing Subsidiary under the Notes, any Subsidiary
Guarantees, the Indenture or this Supplemental Indenture or for any claim based
on, in respect of, or by reason of, such obligations or their creation. Each
Holder of the Notes by accepting a Note waives and releases all such liability.
The waiver and release are part of the consideration for issuance of the Notes.
Such waiver may not be effective to waive liabilities under the federal
securities laws and it is the view of the Commission that such a waiver is
against public policy.

                  7. NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF
NEW YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE BUT
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT
THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED
THEREBY.

                  8. COUNTERPARTS. The parties may sign any number of copies of
this Supplemental Indenture. Each signed copy shall be an original, but all of
them together represent the same agreement.

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                  9. EFFECT OF HEADINGS. The Section headings herein are for
convenience only and shall not affect the construction hereof.

                  10. THE TRUSTEE. The Trustee shall not be responsible in any
manner whatsoever for or in respect of the validity or sufficiency of this
Supplemental Indenture or for or in respect of the recitals contained herein,
all of which recitals are made solely by the Guaranteeing Subsidiaries and the
Company.

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                  IN WITNESS WHEREOF, the parties hereto have caused this
Supplemental Indenture to be duly executed and attested, all as of the date
first above written.

Dated:  October 22, 2003

                                             CREATION GROUP HOLDINGS, INC.

                                             By: /s/ David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             CREATION GROUP, INC.

                                             By: /s/  David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             DURA G.P.

                                             By: Dura Operating Corp.
                                             Its: General Partner

                                             By: /s/  David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             DURA OPERATING CORP.

                                             By: /s/ David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

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                                             DURA AUTOMOTIVE SYSTEMS CABLE
                                             OPERATIONS, INC.

                                             By: /s/ David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             UNIVERSAL TOOL & STAMPING
                                             COMPANY INC.

                                             By: /s/ David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             ADWEST ELECTRONICS, INC.

                                             By: /s/ David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             DURA AUTOMOTIVE SYSTEMS OF
                                             INDIANA, INC.

                                             By: /s/ David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             ATWOOD AUTOMOTIVE INC.

                                             By: /s/ David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

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                                                                    EXHIBIT 4.21

                                             MARK I MOLDED PLASTICS OF
                                             TENNESSEE, INC.

                                             By: /s/ David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             DURA AUTOMOTIVE SYSTEMS, INC.

                                             By: /s/ David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             ATWOOD MOBILE PRODUCTS, INC.

                                             By: /s/  David R. Bovee
                                                 -------------------------------
                                             Name: David R. Bovee
                                             Its: President, Chief Financial
                                                  Officer and Treasurer

                                             BNY MIDWEST TRUST COMPANY, as
                                             Trustee

                                             By: /s/ ROXANE ELLWANGER
                                                 -------------------------------
                                             Name: ROXANE ELLWANGER
                                             Its: ASSISTANT VICE-PRESIDENT