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                                                                    EXHIBIT 4.13

                            SUBORDINATION AGREEMENT

     THIS AGREEMENT is dated as of 14th day of May, 2004 between Joseph Gunnar
& Co., LLC, (the "Representative") as representative of certain note holders
(the "Note Holders") of Tarpon Industries, Inc. under an Agency Appointment
Agreement dated as of April 5, 2004 (the Representative and the Note Holders
are collectively referred to as the "PRINCIPALS") and Greenfield Commercial
Credit (Canada) Inc. ("GREENFIELD");

     WHEREAS Steelbank Inc. (the "CORPORATION") proposes to enter into a
Factoring and Security Agreement and a General Security Agreement (collectively
the "GREENFIELD SECURITY") each between the Corporation and Greenfield made the
14th day of May, 2004 pursuant to which Greenfield agreed to provide certain
financing to Corporation;

     WHEREAS the Corporation has guaranteed repayment of the sum of $2 million
plus interests and other payments by Tarpon Industries, Inc., to the Note
Holders and has granted a security interest in the Corporation's assets
pursuant to the provisions of certain loan documents, guarantees, or other
documents or agreements to be entered into between the Principals (or any one
or more of them) and the Corporation evidencing such loans by or guarantees for
the benefit of the Principals (or any one or more of them) to the Corporation
(collectively, the "PRINCIPAL DOCUMENTS");

     WHEREAS it is desirable that the Principals and Greenfield confirm their
respective priorities as creditors of the Corporation and as secured parties
with respect to the assets of the Corporation.

     NOW THEREFORE THIS AGREEMENT WITNESSES THAT in consideration of the mutual
covenants and agreements herein contained, other good and valuable
consideration and the sum of Two Dollars ($2.00) of lawful money of Canada paid
by and between Greenfield and the Principals (the receipt and sufficiency of
which consideration are hereby acknowledged), the parties hereto agree as
follows:

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                                                                              2.

1.       Postponement of Payment of Principal Debt.

         The Principals hereby postpone payment by the Corporation to the
Principals of all present and future indebtedness and liability now or
hereafter owing by the Corporation to the Principals, whether direct or
indirect, absolute or contingent, matured (by way of acceleration or otherwise)
or unmatured (the "PRINCIPAL DEBT") to and in favour of the payment of all
present and future indebtedness and liability now or hereafter owing by the
Corporation to Greenfield, whether direct or indirect, absolute or contingent,
matured (by way of acceleration or otherwise) or unmatured (collectively, the
"SENIOR DEBT"). Except as permitted under the terms of the Greenfield Security
or this Agreement, the Principals shall not obtain or receive payment of any
amount of the Principal Debt from the Corporation until the Senior Debt has
been fully paid in cash and until Greenfield has no obligation to extend credit
to the Corporation. Notwithstanding the foregoing, the Representative shall be
permitted to receive payment on the Principal Debt from any source other than
the Corporation, and to receive payment from the Corporation of up to the sum
of Can. $250,000.00.

2.       Postponement and Subordination of Security.

         The Principals hereby postpone and subordinate all existing and future
security heretofore, now and hereafter delivered by the Corporation to the
Principals (collectively, the "PRINCIPAL SECURITY") to and in favour of the
Greenfield Security and all existing and future security heretofore, now or
hereafter delivered by the Corporation to Greenfield (collectively, the "SENIOR
SECURITY"). Notwithstanding any priority to which the Principal may be or may
hereafter become entitled for any reason whatsoever (including, without
limitation, priority by date and the time or order of creating, granting or
executing any document, the actual or alleged invalidity or unenforceability of
any of the Senior Security, the perfection of, or the giving of notice or any
demand for payment under the date of advance, registration, publication, filing
or crystallization of or in respect of any charge or encumbrance contained in
the Principal Security and the security interests created thereby or by any
provisions of any relevant law or statute), the Senior Security and all rights
provided thereunder or by law or otherwise shall have full and



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                                                                              3.

absolute priority over and with respect to the Principal Security, and the
Principal Security shall in all respects be postponed and rank subordinate and
junior to the Senior Security and all rights provided thereunder or by law or
otherwise until the parties hereto agree otherwise in writing or all of the
Senior Debt is repaid in full. All liens, charges, security interests and other
encumbrances contained in the Senior Security shall, in all events and under
all circumstances, rank in priority to all liens, charges, security interests
and other encumbrances contained in the Principal Security.

3.       No Enforcement of the Principal Debt and the Principal Security.

         The Principals shall not, without the prior written consent of
Greenfield, claim, demand, sue for, commence any action, commence any
proceeding or take any step (related to, initiating any bankruptcy or
insolvency proceeding until the date on which the Senior Debt has been paid in
full in cash and Greenfield has no obligations to extend credit to the
Corporation but may commence an action to enforce any right of the Principals
against the Corporation pursuant to or in respect of the Principal Debt
provided enforcement of any resulting judgement shall be subject to Section 2
hereof.

4.       Liquidation, Dissolution, Bankruptcy.

         In the event of distribution, division or application, partial or
complete, voluntary or involuntary, by operation of law or otherwise, of all or
any part of the assets of the Corporation, or the proceeds thereof, to creditors
or any proposal by the Corporation to creditors for a readjustment,
reamortization or restructuring of the Senior Debt or the Principal Debt, or
other readjustment of any of the indebtedness or liabilities of the
Corporation, whether by reason of liquidation, bankruptcy, arrangement,
receivership, assignment for the benefit of creditors, marshalling of the
assets or liabilities of the Corporation or any other action or proceeding
involving the readjustment of all or any part of the Senior Debt or the
Principal Debt, or the application of the assets of the Corporation to the
payment of liquidation thereof, or upon the dissolution or other winding-up of
the business of the Corporation, or upon the sale of all or substantially all
of the business of the Corporation, Greenfield shall be entitled to receive
payment in full in cash of the Senior Debt (including interest accruing to the
date of receipt of such payment at the rate applicable to the relevant part of
the Senior Debt, whether or not
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allowed as a claim in any such proceeding) before the Principals are entitled to
receive any direct or indirect payment or distribution of any cash or other
assets of the Corporation on account of the Principal Debt and, to that end,
Greenfield shall be entitled to receive directly, for application in payment of
the Senior Debt (to the extent necessary to pay all Senior Debt in full in cash
after giving effect to any substantially concurrent payment or distribution to
Greenfield in respect of the Senior Debt), any payment or distribution of any
kind or character, whether in cash or other assets, which shall be payable or
deliverable upon or with respect to the Principal Debt. To the extent any
payment of Senior Debt (whether by or on behalf of the Corporation, as proceeds
of security or enforcement of any right of set-off or otherwise) is declared to
be fraudulent or preferential, set aside or required to be paid to a trustee,
receiver, receiver and manager or other similar person under any bankruptcy,
insolvency, receivership or similar law or proceeding, then if such payment is
recoverable by, or paid over to, such trustee, receiver, receiver and manager or
other person, the Senior Debt or part thereof originally intended to be
satisfied shall be deemed to be reinstated and outstanding as if such payment
had not occurred.

5.       Payments Received by the Principal.

         If, notwithstanding the provisions of this Agreement, prior to the
payment in full in cash of the Senior Debt, the Principals (or any one or more
of them) or any person on its behalf receives any payment from or distribution
of assets of the Corporation on account of the Principal Debt, which under the
provisions of this Agreement, the Principals are not specifically authorized to
receive, then the Principals shall, and will ensure that any such other person
shall, receive and hold such payment or distribution in trust for the benefit
of Greenfield and shall promptly pay the same over to Greenfield in precisely
the form received (except for the endorsement or assignment by the Principals
or such other person where necessary) to the extent necessary to pay the Senior
Debt in full after giving effect to any substantially concurrent payment or
distribution to or for the benefit of Greenfield in respect of the Senior Debt.

6.       Notice of Default.

         The Principals shall give to Greenfield notice forthwith of any
default by the Corporation of any of the Corporation's indebtedness, liability
or obligations to any of the
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                                                                              5.


Principal, which notice shall specify all then existing defaults in respect of
such indebtedness, liability or obligations which are known to the Principals.

7.       No Waiver of Subordination Provisions.

         No right of Greenfield to enforce the postponements and subordinations
as herein provided shall at any time in any way be prejudiced or impaired by
any act or failure to act on the part of the Corporation or by any act or
failure to act by Greenfield or any agent of or trustee for Greenfield, or by
any non-compliance by the Corporation with any of the agreements or instruments
relating to the Principal Debt, regardless of any knowledge thereof which
Greenfield may have or be otherwise charged with. Without limitation to the
foregoing, Greenfield may, at any time and from time to time, without the
consent of or notice to the Principals, without incurring responsibility to the
Principals and without impairing or releasing the postponements and
subordinations and other rights or benefits provided in the Agreement or the
obligations hereunder of the Principals to Greenfield, do any one or more of
the following:

    (a)  change the manner, place or terms of payment or change or extend the
         time of payment of, or renew, exchange, amend or alter the terms of
         any Senior Debt, any Senior Security or any guarantee thereof or any
         liability of the Corporation, or any guarantor of the Senior Debt, or
         any liability incurred directly or indirectly in respect thereof, or
         otherwise increase, reduce, amend, alter, renew, exchange, modify or
         supplement in any manner the Senior Debt or any instrument evidencing
         or guaranteeing or securing the same or any agreement under which any
         of the Senior Debt is outstanding;

    (b)  sell, exchange, release, surrender, realize upon, enforce or otherwise
         deal with in any manner any assets pledged or mortgaged for or
         otherwise securing the Senior Debt or any liability of the Corporation
         or any guarantor of the Senior Debt, or any liability incurred directly
         or indirectly in respect thereof;

    (c)  settle or compromise any Senior Debt or any liability of the
         Corporation or any guarantor of the Senior Debt, or any security
         therefor or any liability incurred directly or indirectly in respect
         thereof, and apply any sums by whomsoever paid
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                                                                              6.

          and however realized to any liability (including the Senior Debt) in
          any manner or order; and

     (d)  fail to take or to register or otherwise perfect any lien, mortgage,
          charge or security interest securing the Senior Debt, exercise or
          delay in or refrain from exercising any right or remedy against the
          Corporation or any guarantor of the Senior Debt or any security or any
          other person, and elect any remedy and otherwise deal freely with the
          Corporation and any guarantor of the Senior Debt and with any
          security.

8.        Application of Payments.

          All payments received by Greenfield may be applied, reversed and
reapplied, in whole or in part, to any of the Senior Debt, as Greenfield in its
sole discretion deems appropriate.

9.        Waivers by The Principal.

          All of the Senior Debt shall be deemed to have been made or incurred
and continued in reliance upon this Agreement. The Principals agree that
Greenfield has made no warranties or representations with respect to the due
execution, legality, validity, completeness, perfection or enforceability of
any agreement or instrument relating to the Senior Debt or the collectibility
of the Senior Debt, that Greenfield shall be entitled to manage and supervise
its financial accommodation to the Corporation in accordance with applicable
law and its usual practices, modified from time to time as it deems appropriate
under the circumstances, without regard to the existence of any rights that the
Principals (or any one or more of them) may now or hereafter have in or to any
of the assets of the Corporation, and that Greenfield shall have no liability
to the Principals (or any one or more of them) for, and the Principals hereby
collectively waive any claims which they may now or hereafter have against
Greenfield arising out of, any and all actions which Greenfield, may take or
omit to take (including without limitation actions with respect to the
creation, attachment, perfection or continuation of liens, mortgages, charges
or security interests in any assets at any time securing payment of the Senior
Debt, actions with respect to the occurrence of any default under any agreement
or instrument relating to the Senior Debt, actions with respect to the
foreclosure upon, sale, release or depreciation of, or failure to
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                                                                             7.

realize upon, any assets securing payment of the Senior Debt and actions with
respect to the collection of any claims for all or any part of the Senior Debt
from any account debtor, guarantor or any other person) with respect to the
Senior Debt and any agreement or instrument related thereto or with respect to
the collection of the Senior Debt or the valuation, use, protection or release
of any assets securing payment of the Senior Debt, except actions which are
wrongful or grossly negligent.

10.       Written Waivers.

          No waiver shall be deemed to be made by Greenfield or the Principals
of any of its or his rights hereunder, unless the same shall be in writing
signed by such party, and each waiver, if any, shall (unless specifically
expressed therein to be otherwise) be a waiver only with respect to the specific
instance involved and shall in no way impair the rights of such party or the
obligations of the other party in any other respect or at any other time.

11.       Successors and Assigns.

          The provisions of this Agreement shall be binding on and shall ensure
to the benefit of Greenfield and the Principals and their respective
administrators, executors, heirs, trustees, successors and assigns. The
Principals shall not assign, sell or transfer the Principal Debt or the
Principal Security, or any part thereof, to any person, unless such person
agrees, by agreement in writing with and satisfactory to the Lender, to be
bound by the provisions of this Agreement.

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                                                                              8.

12.  Notices.

     Any notice desired or required to be given under this Agreement shall be
in writing and shall be deemed to have been validly served, given or delivered:
(a) when sent, after receipt of confirmation of transmission by facsimile,
telex or similar transmission; (b) the next business day after deposit with a
reputable overnight courier in Ontario with all charges prepaid; or (c) when
delivered, if hand delivered by messenger, all of which shall be when properly
addressed to the party to be notified and sent to the address or number
indicated as follows:

     If to the Lender:

     Greenfield Commercial Credit (Canada) Inc.
     316 - 20 Queen Street West
     Toronto, Ontario M5H 3R3
     Attention:     Chief Financial Officer
     Facsimile:     416-581-0020

     With a copy to:
     Greenfield Commercial Credit LLC
     300 E. Long Lake Rd., Suite 180
     Bloomfield Hills, Michigan 48304

     Attention:     Credit Manger
     Facsimile:     248-723-6050

     If to the Principals:

     Joseph Gunnar & Co., LLC,
     30 Broad Street
     New York, NY 10004
     Attn: Stephan Stein

     Facsimile: (212) 440-9668

     With a copy to:

     Ruskin Moscou Faltischek, P.C.
     190 EAB Plaza
     East Tower, 15th Floor
     Uniondale, NY 11556
     Attn: Stuart M. Sieger, Esq.

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                                                                             9.

        Facsimile: (516) 663-6746

or to such other address of a party hereto as it may designate to the other
party hereto in the manner herein prescribed.


13.     Entire Agreement: Severability.

        This Agreement contains the entire postponement and subordination
agreement between the parties hereto with respect to the indebtedness,
liabilities and assets of the Corporation. If any of the provisions of this
Agreement shall be held invalid or unenforceable by any court having
jurisdiction, this Agreement shall be construed as if not containing those
provisions, and the rights and obligations of the parties hereto shall be
construed and enforced accordingly.

14.     Cumulative Rights.

        The rights, powers and remedies under this Agreement shall be in
addition to all rights, powers and remedies given by virtue of any statute or
rule of law, or any agreement or instrument, all of which rights, powers and
remedies shall be cumulative and may be exercised successively or concurrently.

15.     Information.

        From time to time upon request therefor, each of the Principals and
Greenfield shall provide to the others such information with respect to the
Corporation and its indebtedness and liabilities as may be reasonably requested.

16.     Governing Law.

        This Agreement shall be governed by and construed in accordance with
the laws of Ontario and the federal laws of Canada applicable therein.
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                                                                             10.

17.  Execution in Counterparts.

     This Agreement may be executed in counterparts, each of which when so
executed shall be deemed to be an original and both of which taken together
shall constitute one and the same agreement.

     IN WITNESS WHEREOF the parties hereto have duly executed this Agreement.


SIGNED, SEALED AND DELIVERED  )  JOSEPH GUNNAR & CO., LLC
in the presence of:           )
                              )  By: /s/ Stephan A. Stein
                              )     ----------------------------------------
                              )  Name: Stephan A. Stein
                              )  Title: Member
----------------------------  )  -------------------------------------------
Witness                       )
                              )

                                 GREENFIELD COMMERCIAL CREDIT
                                 (CANADA) INC.

                                 By: /s/ H. Brock Bundy
                                    ----------------------------------------
                                 Name: H. Brock Bundy
                                 Title: Chief Financial Officer
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TO:      GREENFIELD COMMERCIAL CREDIT (CANADA) INC. ("GREENFIELD")
AND TO:  JOSEPH GUNNAR & CO., LLC as representative of certain Note Holder
         (the "PRINCIPALS")


                              BORROWER'S AGREEMENT

IN CONSIDERATION of the extension of credit by Greenfield to the Corporation,
the Corporation hereby:

1.       consents to the foregoing subordination agreement;

2.       agrees that it will not make any payments to the Principal except as
         may be expressly permitted by the foregoing Senior Security and the
         subordination agreement;

3.       agrees that it shall acquire no rights pursuant to the foregoing
         subordination agreement;

4.       agrees that in order to facilitate any subrogation rights arising
         pursuant to the foregoing subordination agreement, no payments or
         distributions to Greenfield of any cash or other assets to which the
         Principal would have been entitled but for the provisions of the
         foregoing subordination agreement, and no payments over pursuant to the
         provisions of the foregoing subordination agreement made by the
         Principal to Greenfield shall, as between the Corporation and its
         creditors (other than Greenfield be deemed to be a payment or a
         distribution by the Corporation to or on account of the Senior Debt.
         The Corporation shall, as between itself and such creditors, continue
         to owe all such amounts as Senior Debt, it being understood that this
         provision is solely for the purpose of facilitating any subrogation
         rights arising in favour of the Principal pursuant to the foregoing
         subordination agreement; and

         agrees that each of Greenfield and the Principal may provide to the
         other at any time and from time to time any information in its
         possession or control in respect
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         of the Corporation and its affairs including, without limitation,

         notice of any default or impending default.

All words capitalized in this agreement shall have the meanings assigned to them

by the foregoing subordination agreement.

DATED as of the 14th day of May, 2004.


                                  STEELBANK INC.

                                  By: /s/ Barry Seigel
                                      ----------------------------------------
                                  Name:  Barry Seigel
                                  Title: President
                                        (without personal liability whatsoever)