Exhibit 4.1
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                             THIRTEENTH AMENDMENT

                                      TO

                   REVOLVING CREDIT AND TERM LOAN AGREEMENT

                    DATED AS OF APRIL 18, 1997, AS AMENDED

                                 BY AND AMONG

                          NIAGARA LASALLE CORPORATION
                      (FORMERLY NIAGARA COLD DRAWN CORP.)

                             LASALLE STEEL COMPANY

                                      AND

                    MANUFACTURERS AND TRADERS TRUST COMPANY

                         CITIZENS BANK OF PENNSYLVANIA

                        PNC BANK, NATIONAL ASSOCIATION

                                 COMERICA BANK

                                      AND

               MANUFACTURERS AND TRADERS TRUST COMPANY, AS AGENT
                  __________________________________________

                       Effective as of September 1, 2003



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                             THIRTEENTH AMENDMENT
                                      TO
                   REVOLVING CREDIT AND TERM LOAN AGREEMENT


         WHEREAS, NIAGARA LASALLE CORPORATION (formerly NIAGARA COLD DRAWN
CORP.), a Delaware corporation, having its principal office at 110 Hopkins
Street, Buffalo, New York ("NCDC"), LASALLE STEEL COMPANY, a Delaware
corporation, having its principal office at 1412 150th Street, Hammond,
Indiana ("LaSalle") (NCDC and LaSalle being collectively referred to as the
"Borrowers", and individually as a "Borrower"), MANUFACTURERS AND TRADERS
TRUST COMPANY, a New York banking corporation having its principal office at
One M&T Plaza, Buffalo, New York ("M&T"), CIBC INC., a Delaware banking
corporation having its principal office at 425 Lexington Avenue, New York, New
York ("CIBC"), NATIONAL CITY BANK, a Delaware corporation, having its
principal office at National City Center, 1900 East Ninth Street, Cleveland,
Ohio ("National City") and M&T, as administrative, collateral and
documentation agent (M&T to be referred to in such capacity as "Agent"),
entered into a Revolving Credit and Term Loan Agreement dated as of April 18,
1997 (the "Original Agreement", and as subsequently amended as discussed
below, the "Credit Agreement"); and

         WHEREAS, THE PRUDENTIAL INSURANCE COMPANY OF AMERICA, a New Jersey
mutual insurance company having an office at One Gateway Center, Newark, New
Jersey ("Prudential") and NATIONAL BANK OF CANADA, a Canadian chartered bank
having a domestic branch at 125 West 55th Street, New York, New York ("NBC"),
became parties to the Original Agreement by assignment of portions of the
credit commitments of various parties thereto pursuant to Assignment and
Acceptance Agreements dated as of April 18, 1997 and July 22, 1997,
respectively (M&T, CIBC, National City, Prudential and NBC being collectively
referred to herein as the "Banks", and individually as a "Bank"); and

         WHEREAS, the Original Agreement was amended by a First Amendment
dated as of September 4, 1997 for the purpose of, among other things,
providing "Swingline Loans" (as described in the First Amendment) under the
credit facilities provided in the Original Agreement; and

         WHEREAS, the Credit Agreement was further amended by a Second
Amendment dated as of December 31, 1997 for the purpose of, among other
things, (a) permitting the Borrowers to apply the "1993 Warrant Forced
Exercise Net Proceeds Amount" to the repayment of the outstanding and unpaid
principal amount of the "Revolving Credit Note" (as such terms are defined in
the Credit Agreement), and (b) revising the terms of the Credit Agreement with
respect to dividends; and

         WHEREAS, the Credit Agreement was further amended by a Third
Amendment effective as of May 15, 1998 for the purpose of, among other things,
(a) reducing the interest payable with respect to "LIBOR Rate Loans" (as
defined in the Credit Agreement), and (b) providing for the further reduction
of the interest payable with respect to LIBOR Rate Loans upon the conclusion
of a new collective bargaining agreement with LaSalle's hourly employees in
Hammond, Indiana; and

         WHEREAS, the Credit Agreement was further amended by a Fourth
Amendment effective as of December 1, 1998 for the purpose of, among other
things, increasing by One Million Dollars ($1,000,000) the amount of permitted
"Capital Expenditures" (as defined in the Credit Agreement) that may be made
by the Borrowers in any "Fiscal Year" (as defined in the Credit Agreement);
and

         WHEREAS, the Credit Agreement was further amended by a Fifth
Amendment effective as of May 21, 1999, for the purpose of, among other
things, (a) waiving the requirement for mandatory repayment of principal from
"Excess Cash Flow" (as defined in the Credit Agreement) for the Fiscal Year
ended December 31, 1998, and (b) in connection with a proposed business
acquisition by a UK subsidiary of Niagara Corporation, permitting the
Borrowers to provide guaranties to certain banks providing standby letters of
credit to support acquisition financing to such UK subsidiary; and

         WHEREAS, the Credit Agreement was further amended by a Sixth
Amendment effective as of December 31, 1999 for the purpose of, among other
things, (a) reducing the required ratio of Consolidated Current Assets to
Consolidated Current Liabilities, (b) changing the definition of "Majority
Banks" (as defined in the Credit Agreement), (c) clarifying the requirement
that the consent of the Majority Banks is required in connection with any
amendment or waiver of any provision of the Credit Agreement, and (d)
extending the termination date of the Revolving Credit Commitment and the
Revolving Credit Note to April 17, 2001; and

         WHEREAS, CITIZENS BUSINESS CREDIT COMPANY, having an office at Six
PPG Place, Suite 820, Pittsburgh, Pennsylvania ("Citizens"), became a party to
the Credit Agreement, as amended by the foregoing, by assignment of the entire
credit commitments of National City (Citizens, as assignee, to be referred to
as a "Bank" for all purposes hereof) pursuant to an Assignment and Acceptance
Agreement dated as of February 1, 2000;

         WHEREAS, the Credit Agreement was further amended by a Seventh
Amendment effective as of March 31, 2000 for the purpose of, among other
things, increasing the aggregate amount of all payments under all Capitalized
Leases and payments under operating leases, equipment leases or other leases
of real or personal property that may be made by Borrowers and their
Subsidiaries in any Fiscal Year without the prior written consent of the
Agent; and

         WHEREAS, the Credit Agreement was further amended by an Eighth
Amendment effective as of June 8, 2000 for the purpose of, among other things,
extending the termination date of the Revolving Credit Commitment and the
Revolving Credit Note to April 18, 2002; and

         WHEREAS, the Credit Agreement was further amended by a Ninth
Amendment effective as of June 28, 2001 for the purpose of, among other
things, (a) extending the termination date of the Revolving Credit Commitment
and the Revolving Credit Note to December 31, 2002, (b) increasing the
interest payable with respect to "LIBOR Rate Loans" (as defined in the Credit
Agreement), and (c) clarifying that the limitation on the amount that may be
provided to Niagara Corporation (the parent company of the Borrowers) as a
dividend is intended to include the proceeds of loans made under the Revolving
Credit Facility that may be advanced to Niagara Corporation; and

         WHEREAS, the Credit Agreement was further amended by a Tenth
Amendment effective as of December 31, 2001 for the purpose of, among other
things, (a) extending the termination date of the Revolving Credit Commitment
and the Revolving Credit Note to July 31, 2003, (b) increasing the interest
payable with respect to "Loans" (as such term is defined in the Credit
Agreement), and (c) reducing the required ratio of Consolidated Current Assets
to Consolidated Current Liabilities (as such terms are defined in the Credit
Agreement); and

         WHEREAS, PNC BANK, NATIONAL ASSOCIATION, a national banking company
having an office at One PNC Plaza, 249 Fifth Avenue, Pittsburgh, Pennsylvania
("PNC"), became a party to the Credit Agreement, as amended by the foregoing,
by assignment of the entire credit commitments of National Bank of Canada
(PNC, as assignee, to be referred to as a "Bank" for all purposes hereof)
pursuant to an Assignment and Acceptance Agreement dated as of January 15,
2002; and

         WHEREAS, COMERICA BANK, a national banking company having an office
at Comerica Tower at Detroit Center, 500 Woodward Avenue, Detroit, Michigan
("Comerica"), became a party to the Credit Agreement, as amended by the
foregoing, by assignment of the entire credit commitments of CIBC (Comerica,
as assignee, to be referred to as a "Bank" for all purposes hereof) pursuant
to an Assignment and Acceptance Agreement dated as of March 28, 2002; and

         WHEREAS, the Credit Agreement was further amended by an Eleventh
Amendment effective as of April 1, 2002 for the purpose of, among other
things, (a) changing the definition of "Eligible Inventory" (as defined in the
Credit Agreement) to include work-in-process, (b) deleting the interest
coverage ratio financial covenant and replacing it with a debt service
coverage ratio financial covenant, (c) modifying the net worth financial
covenant, and (d) adding a secured indebtedness covenant; and

         WHEREAS, pursuant to Assignment and Acceptance Agreements dated as of
August 15, 2002 by and between Prudential and each of M&T, Comerica and PNC,
Prudential assigned its entire credit commitments to such Banks; and

         WHEREAS, the Credit Agreement was further amended by a Twelfth
Amendment effective as of September 1, 2002 for the purpose of, among other
things, (a) reducing the Revolving Credit Commitment (as such term is defined
in the Credit Agreement) from $50,000,000 to $35,000,000, (b) extending the
Revolving Credit Termination Date (as such term is defined in the Credit
Agreement) to July 31, 2004, (c) increasing the Term Loan Commitment (as such
term is defined in the Credit Agreement) from $14,333,356 to $18,000,000, (d)
extending the Maturity Date (as such term is defined in the Credit Agreement)
to July 31, 2004, and (e) revising the amortization schedule and principal
repayment schedule of the Term Loan; and

         WHEREAS, Citizens Bank of Pennsylvania, having an office at Six PPG
Place, Suite 820, Pittsburgh, Pennsylvania ("Citizens Bank") became a party to
the Credit Agreement, as amended by the foregoing, by assignment of the entire
credit commitments of Citizens (Citizens Bank, as assignee, to be referred to
as a "Bank" for all purposes hereof) pursuant to an Assignment and Acceptance
Agreement dated as of March 1, 2003; and

         WHEREAS, the Borrowers have requested that the Agent and the Banks
further amend the Credit Agreement for the purpose of, among other things, (a)
extending the Revolving Credit Termination Date (as such term is defined in
the Credit Agreement) to July 31, 2006, (b) extending the Maturity Date (as
such term is defined in the Credit Agreement) to July 31, 2006, (c) revising
the amortization and principal repayment schedule of the Term Loan and (d)
revising the Use of Proceeds covenant set forth in the Credit Agreement..

         NOW, THEREFORE, the parties hereto hereby agree as follows:

         1. Definitions. Subsection 1.1 of the Credit Agreement shall be
amended as follows:

               a. Each reference to the date "July 31, 2004" in the definition
of "Revolving Credit Termination Date" contained in Subsection 1.1 of the
Credit Agreement is hereby deleted in its entirety and replaced with the date
"July 31, 2006"; and

         2. Amendment of Term Loan Maturity Date. Subsection 2.2(b) of the
Credit Agreement is hereby deleted in its entirety and replaced with the
following:

               "(b) Term Loan Note. The Term Loan shall be evidenced by, and
repaid with interest in accordance with, a single promissory note of the
Borrowers in form and content acceptable to Agent, as the same may be amended
or replaced from time to time ("Term Loan Note"). Interest on the outstanding
and unpaid principal amount of the Term Loan Note will be payable from the
date of the Term Loan Note as hereinafter provided, and the principal amount
of the Term Loan Note shall be repaid in thirty-five (35) equal and
consecutive monthly installments commencing September 1, 2003 with subsequent
installments being due on the first day of each calendar month thereafter and
one final installment due and payable on or before July 31, 2006 (the
"Maturity Date") in the amount necessary to repay in full the unpaid principal
amount of the Term Loan Note.

         The amount of each installment of principal repayment of the Term
Loan shall be as follows:

     Installment Date                        Principal Repayment
     ----------------                        -------------------

September 1, 2003 through
and including July 1, 2006                           $375,000

July 31, 2006                                Outstanding Balance of Term Loan

         3. Amendment of Use of Proceeds Affirmative Covenant. The last
sentence of Section 5.14 of the Credit Agreement is hereby deleted in its
entirety and replaced with the following:

         "Additionally, the Borrowers represent to and covenant with the Banks
that the proceeds of each Revolving Credit Loan not used pursuant to the
preceding sentence shall be used (i) to fund the general working capital
purposes of the Borrowers and their Subsidiaries, (ii) to fund letters of
credit issued for the account of the Borrowers and their Subsidiaries, (iii)
to the extent permitted by the terms of Subsection 6.10(h) hereof, fund the
amount of any loan made by the Borrowers to Niagara, or (iv) to the extent
permitted by the terms of Subsection 6.12(b) hereof, to fund repayment to
Niagara of amounts applied by Niagara as Excess Warrant Proceeds to repay the
outstanding and unpaid principal amount of the Revolving Credit Note or to
prepay the outstanding and unpaid principal amount of the Term Loan Note
pursuant to Subsection 2.11 hereof."

         4. This Thirteenth Amendment shall be effective as of September 1,
2003.

         5. All capitalized terms used herein (including the introductory
recitations above), unless otherwise defined herein, have the same meaning
provided therefor in the Credit Agreement.

         6. The amendments set forth herein are limited precisely as written
and shall not be deemed to (a) be a consent to or a waiver of any other term
or condition of the Credit Agreement or any of the documents referred to
therein, or (b) prejudice any right or rights which the Agent or any Bank may
now have or may have in the future under or in connection with the Credit
Agreement or any documents referred to therein. Whenever the Credit Agreement
is referred to in the Credit Agreement or in any of the instruments,
agreements or other documents or papers executed and delivered in connection
therewith, it shall be deemed to mean the Credit Agreement as modified by all
amendments thereto, including this Thirteenth Amendment.

         7. The Borrowers hereby represent and warrant, jointly and severally,
that upon giving effect to the terms and provisions of this Thirteenth
Amendment no default or Event of Default shall have occurred and be continuing
under the terms of the Credit Agreement.

         8. This Thirteenth Amendment may be executed by one or more of the
parties to this Thirteenth Amendment on any number of separate counterparts
and all of said counterparts taken together shall be deemed to constitute one
and the same instrument.


         IN WITNESS WHEREOF, the parties hereto have caused this Thirteenth
Amendment to be duly executed and delivered by their respective duly
authorized officers.


                                            NIAGARA LASALLE CORPORATION


                                            By: /s/ Marc J. Segalman
                                                ----------------------------
                                            Name:  Marc J. Segalman
                                            Title: EVP & General Counsel


                                            LASALLE STEEL COMPANY

                                            By: /s/ Marc J. Segalman
                                                ----------------------------
                                            Name:  Marc J. Segalman
                                            Title: EVP & General Counsel


                                            MANUFACTURERS AND TRADERS TRUST
                                            COMPANY

                                            By: /s/ Robert J. Kush
                                                ----------------------------
                                            Name:  Robert J. Kush
                                            Title: Vice President


                                            CITIZENS BANK OF PENNSYLVANIA


                                            By: /s/ Donald Cmar
                                                ---------------------------
                                            Name:  Donald Cmar
                                            Title: Vice President


                                            PNC BANK, NATIONAL ASSOCIATION


                                            By: /s/ Stephen W. Boyd
                                                ---------------------------
                                            Name:  Stephen W. Boyd
                                            Title: Vice President


                                            COMERICA BANK

                                            By: /s/ Richard S. Bagosy
                                                ---------------------------
                                            Name:  Richard S. Bagosy
                                            Title: Vice President


                                            MANUFACTURERS AND TRADERS TRUST
                                            COMPANY, AS AGENT


                                            By: /s/ Robert J. Kush
                                                ---------------------------
                                            Name:  Robert J. Kush
                                            Title: Vice President


ACKNOWLEDGMENT

By executing below, Niagara Corporation hereby consents and agrees to the
terms and conditions contained in this Thirteenth Amendment and hereby
reaffirms its obligations and liabilities pursuant to the terms of the
Unconditional and Continuing Guaranty Agreement by and between Niagara
Corporation and Manufacturers and Traders Trust Company, as Agent dated as of
April 18, 1997, as amended from time to time.

NIAGARA CORPORATION


By: /s/ Marc J. Segalman
    ---------------------------
Name:  Marc J. Segalman
Title: EVP & General Counsel