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                                                                     EXHIBIT 4.1

                       THIRD AMENDMENT TO CREDIT AGREEMENT


         This THIRD AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is made and
entered into as of December 31, 2005 (the "Effective Date"), by and among METAL
MANAGEMENT, INC., a Delaware corporation, CIM TRUCKING, INC., an Illinois
corporation, MTLM ARIZONA, INC., an Arizona corporation, MAC LEOD METALS CO., a
California corporation, METAL MANAGEMENT AEROSPACE, INC., a Delaware
corporation, METAL MANAGEMENT ALABAMA, INC., a Delaware corporation, METAL
MANAGEMENT ARIZONA, L.L.C., an Arizona limited liability company, METAL
MANAGEMENT CONNECTICUT, INC., a Delaware corporation, METAL MANAGEMENT GULF
COAST, INC., a Delaware corporation, METAL MANAGEMENT INDIANA, INC., an Illinois
corporation, METAL MANAGEMENT MEMPHIS, L.L.C., a Tennessee limited liability
company, METAL MANAGEMENT MIDWEST, INC., an Illinois corporation, METAL
MANAGEMENT MISSISSIPPI, L.L.C., a Delaware limited liability company, METAL
MANAGEMENT NEW HAVEN, INC., a Delaware corporation, METAL MANAGEMENT NORTHEAST,
INC., a New Jersey corporation, METAL MANAGEMENT OHIO, INC., an Ohio
corporation, METAL MANAGEMENT PITTSBURGH, INC., a Delaware corporation, METAL
MANAGEMENT S&A HOLDINGS, INC., a Delaware corporation, METAL MANAGEMENT
STAINLESS & ALLOY, INC., a Delaware corporation, METAL MANAGEMENT WEST, INC., a
Colorado corporation, METAL MANAGEMENT WEST COAST HOLDINGS, INC., a Delaware
corporation, NAPORANO IRON & METAL, INC. (f/k/a Metal Management Services,
Inc.), a Delaware corporation, PROLER SOUTHWEST LP, a Texas limited partnership
(formerly a Texas corporation known as Proler Southwest Inc.), and RESERVE IRON
& METAL LIMITED PARTNERSHIP, a Delaware limited partnership (collectively, the
"Existing Borrowers"); METAL MANAGEMENT, INC., a Delaware corporation, acting in
its capacity as borrowing agent and funds administrator for the Borrowers (in
such capacity, the "Funds Administrator"); PROLER SOUTHWEST GP, INC., a Delaware
corporation ("Proler GP"); METAL MANAGEMENT PROLER SOUTHWEST, INC., a Delaware
corporation ("Proler LP", and collectively with Proler GP and the Existing
Borrowers, the "Borrowers"); the financial institutions identified on the
signature pages hereto as lenders (the "Lenders"); and LASALLE BANK NATIONAL
ASSOCIATION, a national banking association acting in its capacity as agent for
the Lenders (in such capacity, "Agent").

         WHEREAS, the Existing Borrowers, the Funds Administrator, the Lenders
and the Agent are party to a certain Credit Agreement dated as of June 28, 2004,
as amended by a certain First Amendment to Credit Agreement dated as of March 1,
2005 and a certain Second Amendment to Credit Agreement dated as of May 9, 2005
(such Credit Agreement, as amended by such First Amendment and Second Amendment,
as it may be from time to time amended, restated, modified, or supplemented, the
"Credit Agreement");

         WHEREAS, Metal Management, Inc. has caused its direct or indirect
wholly owned subsidiary, Proler Southwest Inc., a Texas corporation, to be
converted into a Texas limited partnership known as Proler Southwest LP ("Proler
Southwest LP") in accordance with the provisions of Article 5.17 of the Texas
Corporation Act and Section 2.15 of the Texas Revised Limited Partnership Act;
and

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         WHEREAS, in connection with the conversion of Proler Southwest Inc. to
Proler Southwest LP, MTLM has caused to be formed Proler GP and Proler LP, each
a wholly owned direct or indirect subsidiary of MTLM, and has caused Proler GP
and Proler LP to become, respectively, the sole general partner and the sole
limited partner of Proler Southwest LP; and

         WHEREAS, in accordance with Texas law, Proler Southwest LP has
succeeded to all obligations and liabilities of Proler Southwest Inc. under and
in connection with the Credit Agreement and the other Credit Documents, and
Proler Southwest desires to so confirm such obligations and liabilities, and
Proler GP and Proler LP desire to join the Credit Agreement as "Borrowers"
thereunder; and

         WHEREAS, the defined terms used, but not defined, herein shall have the
meanings ascribed to such terms in the Credit Agreement.

         NOW, THEREFORE, for valuable consideration received to their mutual
satisfaction, the parties hereby agree as follows:

         1.  Confirmation and Assumption by Proler Southwest LP. Proler
Southwest LP hereby confirms, agrees and acknowledges that all liabilities and
obligations of Proler Southwest Inc. under and in connection with the Credit
Agreement and the other Credit Documents continue to be and are liabilities and
obligations of Proler Southwest LP without impairment or diminution of any kind.

         2.  Joinder by Proler GP and Proler LP. Each of Proler GP and Proler LP
hereby agrees to join and become a party to the Credit Agreement and each other
of the Credit Documents in the capacity of "Borrower" (or similarly designated
capacity, as applicable) thereunder, and hereby assumes and agrees to perform
all obligations thereunder.

         3.  Security Agreement; UCC Financing Statements. Each of Proler GP,
Proler LP and Proler Southwest LP hereby acknowledges and agrees that it is
bound by and hereby confirms and joins the terms of the Security Agreement as a
"Grantor" thereunder. Each of Proler GP, Proler LP and Proler Southwest LP
acknowledges and agrees that Agent and its agents are authorized to file such
Uniform Commercial Code financing statements and amendments thereto covering the
Collateral or any portion thereof in such jurisdictions as Agent may deem
desirable without further authentication by the such entities, and each such
entity does hereby ratify, confirm, acknowledge, authorize and authenticate any
such financing statements heretofore filed. With respect to each of Proler GP,
Proler LP and Proler Southwest LP, following is (i) the exact legal name of such
entity as it appears on the organizational documents of such entity, (ii) the
address of the chief executive office and principal place of business of such
entity, (iii) the jurisdiction of incorporation or formation of such entity, and
(iv) the organizational identification number of such entity:

             Exact Legal Name:  Proler Southwest GP, Inc.
             Jurisdiction of Incorporation:  Delaware
             Address:  90 Hirsch Road
                       Houston, Texas 77020
             Organizational Number:  4072321


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             Exact Legal Name:  Metal Management Proler Southwest, Inc.
             Jurisdiction of Organization:  Delaware
             Address:  325 North LaSalle Street, Suite 550
                       Chicago, Illinois 60610
             Organizational Number:  4072322

             Exact Legal Name:  Proler Southwest LP
             Jurisdiction of Organization:  Texas
             Address:  90 Hirsch Road
                       Houston, Texas 77020
             Organizational Number:  800585413

Except as set forth above, none of Proler GP, Proler LP or Proler Southwest LP
has been known by any other name, including trade names (except that Proler
Southwest LP was previously known as Proler Southwest Inc.) or maintained its
chief executive office and principal place of business at any other location
during the preceding five (5) years. To the extent that financing statements
have been filed against Proler GP, Proler LP and Proler Southwest LP in
appropriate offices, Agent will have a fully perfected first priority security
interest in the such Borrowers' interest in Collateral in which a security
interest may be perfected by filing, subject only to Permitted Liens, and
neither such security interest nor the exercise of any rights therein would
contravene, violate, constitute a default under or require the consent of any
other person or entity under any contract, agreement, indenture, instrument or
undertaking binding upon or enforceable against any Borrower, including without
limitation, the Governing Documents of Proler GP, Proler LP or Proler Southwest
LP

         4.  Delivery of Stock Certificates. MTLM represents and warrants that
it owns one-hundred percent (100%) of the issued and outstanding capital stock
of each of Proler GP and Proler LP, free and clear of any liens, claims or
encumbrances, except for the lien in favor of Agent. MTLM shall cause to be
delivered to Agent the original stock certificate(s) evidencing MTLM's ownership
of one-hundred percent (100%) of the issued capital stock of each of Proler GP
and Proler LP, together with duly executed stock powers in blank. Upon delivery
of such stock certificate(s), Agent will have a fully perfected first priority
interest therein.

         5.  Representation and Warranty Regarding Partnership Interests. The
Borrowers and the Funds Administrator represent, warrant, covenant and agree
that the Borrowers' interest in Proler Southwest LP is and shall at all times be
represented by Partnership Interests (as such term is defined in the Security
Agreement) owned directly by MTLM or by one or more of the other Borrowers and
that such Partnership Interests are not and shall not be represented any
certificates, documents or instruments of any kind without the prior written
consent of the Agent (unless the originals of such certificates are delivered to
Agent with duly executed instruments of transfer in blank).

         6.  General Terms of Amendment. Except as specifically amended herein,
directly or by reference, all of the terms and conditions set forth in the
Credit Agreement and the other Credit Documents are confirmed and ratified, and
shall remain as originally written. This Amendment shall be construed in
accordance with the laws of the State of Illinois, without regard to principles
of conflict of laws. Nothing herein shall affect or impair any rights and


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powers which the Borrowers, the Funds Administrator, any Lender or the Agent may
have under the Credit Agreement or any of the other Credit Documents.

         7.  Release. In consideration of this Amendment, the Borrowers and the
Funds Administrator hereby release and discharge the Lenders and Agent and each
of their respective shareholders, directors, officers, employees, attorneys,
affiliates and subsidiaries from any and all claims, demands, liability and
causes of action whatsoever, now known or unknown, arising prior to the date
hereof out of or in any way related to the extension or administration of the
Obligations, the Credit Agreement, the other Credit Documents or any security
interest related thereto.

         8.  Liens not Impaired. The parties hereto further agree that this
Amendment shall in no manner affect or impair the liens and security interests
evidenced by the Credit Agreement and/or any other Credit Documents or
instruments evidencing, securing or related to the Obligations. The Borrowers
hereby acknowledge that all liens and security interests securing the
Obligations are valid and subsisting.

         9.  No Counterclaims or Defenses. The Borrowers and the Funds
Administrator hereby declare that neither the Borrowers nor the Funds
Administrator have any set offs, counterclaims, defenses or other causes of
action against the Lenders or the Agent arising out of the Credit Agreement, the
other Credit Documents or the transactions contemplated thereby, and to the
extent any such set offs, counterclaims, defenses or other causes of action
might exist, such items are hereby waived by the Borrowers.

         10. Representations and Undertakings of Borrowers and Funds
Administrator. Each of the Borrowers and the Funds Administrator hereby
represents and warrants to the Lenders and the Agent that: (a) each Credit Party
a party hereto has the legal power and authority to execute and deliver this
Amendment; (b) the officers or representatives executing this Amendment have
been duly authorized to execute and deliver the same and bind such Credit
Parties with respect to the provisions hereof; (c) the execution and delivery
hereof by such Credit Parties and the performance and observance by such Credit
Parties of the provisions hereof do not violate or conflict with the
organizational documents or agreements of such Credit Parties or any law
applicable to such Credit Parties or result in a breach of any provisions of or
constitute a default under any other agreement, document, certificate or
instrument binding upon or enforceable against such Credit Parties; (d) this
Amendment constitutes a valid and binding obligation upon such Credit Parties in
every respect, and (e) the recitals to this Amendment are true and correct. The
Borrowers and the Funds Administrator hereby further represent and warrant to
the Lenders and the Agent that no Default or Event of Default has occurred under
the Credit Agreement or the other Credit Documents and that each of the
representations and warranties of the Borrowers and the Funds Administrator set
forth in the Credit Agreement and the other Credit Documents are true and
correct as of the Effective Date.

         11. Conditions Precedent. The effectiveness of this Amendment is
subject to delivery to Agent of the following in form and substance satisfactory
to Agent:

         (a) A Certificate of Secretary or Assistant Secretary of Proler GP
             setting forth true and correct copies of the certificate of
             incorporation of Proler GP as certified by


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             the Secretary of State of Delaware, the bylaws of Proler GP, a
             certificate of good standing issued by the State of Delaware and
             evidence of foreign qualification in each other state in which
             Proler GP is required to be so qualified, incumbency statement, and
             resolutions authorizing the actions taken herein (on its own behalf
             and as general partner on behalf of Proler Southwest LP).

         (b) A Certificate of Secretary or Assistant Secretary of Proler LP
             setting forth true and correct copies of the certificate of
             incorporation of Proler LP as certified by the Secretary of State
             of Delaware, the bylaws of Proler LP, a certificate of good
             standing issued by the State of Delaware and evidence of foreign
             qualification in each other state in which Proler LP is required to
             be so qualified, incumbency statement, and resolutions authorizing
             the actions taken herein (on its own behalf and, to the extent
             required, as limited partner of Proler Southwest LP).

         (c) A Certificate of General Partner of Proler Southwest LP setting
             forth true and correct copies of the certificate of limited
             partnership of Proler Southwest LP as certified by the Secretary of
             State of Texas, the agreement of limited partnership of Proler
             Southwest LP, a certificate of good standing or existence or
             equivalent, issued by the State of Texas, the articles of
             conversion of Proler Southwest Inc. into Proler Southwest LP as
             certified by the Secretary of State of Texas, and the agreement of
             conversion of Proler Southwest Inc. into Proler Southwest LP.

         (d) The original stock certificate(s) evidencing one-hundred percent
             (100%) of the issued and outstanding capital stock of each of
             Proler GP and Proler LP, together with stock powers in blank to
             Agent duly executed by the holders thereof.

         (e) The favorable opinion of counsel to Proler GP, Proler LP and Proler
             Southwest LP (i) with respect to Proler GP and Proler LP, as to due
             existence, good standing, foreign qualification as applicable,
             authority, due execution and delivery, non-contravention and lack
             of need to be registered under the Investment Company Act, and (ii)
             with respect to Proler Southwest LP, as to due existence, good
             standing, authority, due execution and delivery, non-contravention
             and lack of need to be registered under the Investment Company Act,
             and with respect to the conversion, that the conversion has been
             completed and that Proler Southwest LP has succeeded to all
             obligations and liabilities of Proler Southwest Inc. under and in
             connection with the Credit Agreement and the other Credit Documents
             under Texas law.

         (f) With regard to each Credit Party other than Proler GP, Proler LP
             and Proler Southwest, certified copies of resolutions of such
             Credit Parties authorizing the execution, delivery and performance
             of this Amendment by such Credit Parties, certification that there
             have been no amendments to the respective bylaws, certificates of
             incorporation or equivalent constituent documents of the Credit
             Parties since the date of the original Credit Agreement (or if
             there have been such amendments, certified copies of such amended
             documents) and an incumbency certificate evidencing the authority
             of the officers of such Credit Parties executing this Amendment.


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         12. Costs and Expenses. The Borrowers and the Funds Administrator
jointly and severally agree to pay, on demand, all costs and expenses of the
Agent (including the reasonable fees and expenses of outside counsel for the
Agent) in connection with the preparation, negotiation, execution, delivery, and
administration of this Amendment and any other Credit Documents and all other
instruments or documents provided for herein or delivered or to be delivered
hereunder or in connection herewith or related thereto. In addition, the
Borrowers and the Funds Administrator jointly and severally agree to pay, and
save the Lenders and the Agent harmless from all liability for, any stamp or
other taxes which may be payable in connection with the execution or delivery of
this Amendment, the borrowings contemplated in this Amendment, and the execution
and delivery of any instruments or documents provided for herein or delivered or
to be delivered hereunder or in connection herewith or in connection with the
Credit Agreement or the other Credit Documents. All obligations in this Section
shall survive any termination of the Credit Agreement, as amended hereby, and
the other Credit Documents. The Borrowers and the Funds Administrator hereby
authorize the Agent to charge the Borrowers' account(s) with the Agent in
respect of any and all costs and expenses described hereunder.

         13. Section Titles. The Section titles and captions contained herein
are and shall be without substantive meaning and are not a part of the agreement
between the parties hereto.

         14. Counterparts. This Amendment may be executed in counterparts and
all such counterparts shall constitute one agreement binding on all the parties,
notwithstanding that the parties are not signatories to the same counterpart.

                            [Signature Pages Follow]



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         IN WITNESS WHEREOF, the respective parties hereto have caused this
Third Amendment to Credit Agreement to be executed and delivered by their duly
authorized officers as of the date first set forth above.

                 METAL MANAGEMENT, INC.,
                 as Funds Administrator and as Borrower

                 By: /s/ Robert C. Larry
                     -----------------------------------
                     Name:  Robert C. Larry
                     Title: Executive Vice President and Chief Financial Officer

                 ADDITIONAL BORROWERS:

                 CIM TRUCKING, INC.
                 MACLEOD METALS CO.
                 MTLM ARIZONA, INC.
                 METAL MANAGEMENT AEROSPACE, INC.
                 METAL MANAGEMENT ALABAMA, INC.
                 METAL MANAGEMENT ARIZONA, L.L.C.
                 METAL MANAGEMENT CONNECTICUT, INC.
                 METAL MANAGEMENT GULF COAST, INC.
                 METAL MANAGEMENT INDIANA, INC.
                 METAL MANAGEMENT MEMPHIS, L.L.C.
                 METAL MANAGEMENT MIDWEST, INC.
                 METAL MANAGEMENT MISSISSIPPI, L.L.C.
                 METAL MANAGEMENT NEW HAVEN, INC.
                 METAL MANAGEMENT NORTHEAST, INC.
                 METAL MANAGEMENT OHIO, INC.
                 METAL MANAGEMENT PITTSBURGH, INC.
                 METAL MANAGEMENT S&A HOLDINGS, INC.
                 METAL MANAGEMENT STAINLESS & ALLOY, INC.
                 METAL MANAGEMENT WEST, INC.
                 METAL MANAGEMENT WEST COAST HOLDINGS, INC.
                 NAPORANO IRON & METAL, INC.

                 By: /s/ Robert C. Larry
                     -----------------------------------
                     Name:  Robert C. Larry
                     Title: Vice President

                 RESERVE IRON & METAL LIMITED PARTNERSHIP

                 By: METAL MANAGEMENT OHIO, INC., its general partner

                 By: /s/ Robert C. Larry
                     -----------------------------------
                     Name:  Robert C. Larry
                     Title: Vice President

                           [Signature Page Continues]


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                 [Signature Page to Third Amendment, Continued]

                 PROLER SOUTHWEST GP, INC.


                 By: /s/ Amit N. Patel
                     -----------------------------------
                     Name:  Amit N. Patel
                     Title: Vice President & Chief Financial Officer


                 METAL MANAGEMENT PROLER SOUTHWEST, INC.


                 By: /s/ Amit N. Patel
                     -----------------------------------
                     Name:  Amit N. Patel
                     Title: Vice President & Chief Financial Officer


                 PROLER SOUTHWEST LP


                 By: PROLER SOUTHWEST GP, INC., its general partner

                 By: /s/ Amit N. Patel
                     -----------------------------------
                     Name:  Amit N. Patel
                     Title: Vice President & Chief Financial Officer



                           [Signature Page Continues]


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                 [Signature Page to Third Amendment, Continued]

                 AGENT:

                 LASALLE BANK NATIONAL ASSOCIATION, as Agent


                 By: /s/ Michael J. Vrchota
                     -----------------------------------
                     Name:  Michael J. Vrchota
                     Title: First Vice President


                 LENDERS:

                 LASALLE BANK NATIONAL ASSOCIATION


                 By: /s/ Michael J. Vrchota
                     -----------------------------------
                     Name:  Michael J. Vrchota
                     Title: First Vice President


                           [Signature Page Continues]


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                 [Signature Page to Third Amendment, Continued]

                 PNC BANK NATIONAL ASSOCIATION


                 By: /s/ John M. Cunningham
                     -----------------------------------
                     Name:  John M. Cunningham
                     Title: Vice President


                           [Signature Page Continues]



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                 [Signature Page to Third Amendment, Continued]

                 SOVEREIGN BANK


                 By  /s/ Robert E. Cook
                     -----------------------------------
                     Name:  Robert E. Cook
                     Title: Vice President


                           [Signature Page Continues]



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                 [Signature Page to Third Amendment, Continued]

                 U.S. BANK, NATIONAL ASSOCIATION


                 By: /s/ Matthew J. Schulz
                     -----------------------------------
                     Name:  Matthew J. Schulz
                     Title: Vice President



                           [Signature Page Continues]


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                 [Signature Page to Third Amendment, Continued]

                 NATIONAL CITY BANK OF THE MIDWEST


                 By: /s/ James M. Kershner
                     -----------------------------------
                     Name:  James M. Kershner
                     Title: Vice President


                           [Signature Page Continues]


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                 [Signature Page to Third Amendment, Continued]

                 FIFTH THIRD BANK


                 By: /s/ Susan M. Kaminski
                     -----------------------------------
                     Name:  Susan M. Kaminski
                     Title: Vice President


                           [Signature Page Continues]


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                 [Signature Page to Third Amendment, Continued]

                 KEYBANK NATIONAL ASSOCIATION


                 By: /s/ Suzannah Harris
                     -----------------------------------
                     Name:  Suzannah Harris
                     Title: Assistant Vice President


                           [Signature Page Continues]


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                 [Signature Page to Third Amendment, Continued]

                 RZB FINANCE LLC


                 By: /s/ John A. Valiska
                     -----------------------------------
                     Name:  John A. Valiska
                     Title: First Vice President


                 By: /s/ Christoph Hoedl
                     -----------------------------------
                     Name:  Christoph Hoedl
                     Title: Group Vice President



                           [Signature Page Continues]


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                 [Signature Page to Third Amendment, Continued]

                 CHARTER ONE BANK, N.A.


                 By: /s/ William D. Ryan
                     -----------------------------------
                     Name:  William D. Ryan
                     Title: Senior Vice President