NOTE AGREEMENT

Exhibit 4.4(iv)

BARNES GROUP INC.

AMENDMENT NO. 3 TO NOTE AGREEMENT

As of January 11, 2006

To each of the Current Noteholders

Named in Annex 1 hereto

Ladies and Gentlemen:

Barnes Group Inc. , a Delaware corporation (hereinafter, the “ Company ”), together with its successors and assigns, agrees with you as follows:

The Company issued and sold $60,000,000 aggregate principal amount of its 8.59% Senior Notes due November 21, 2008 (as may be amended, restated or otherwise modified from time to time, the “ Notes ”) pursuant to separate Note Agreements, each dated as of November 21, 2000, entered into by and among the Company and each of the Purchasers listed on Exhibit A attached thereto, as amended by Amendment No. 1 to Note Agreement, dated as of February 21, 2002 between the Company and each of the Persons identified on Annex 1 attached thereto, and Amendment No. 2, dated as of February 5, 2003 between the Company and each of the Persons identified on Annex 1 attached thereto (the “ Existing Note Agreement ” and, as amended by this Amendment No. 3 to Note Agreement (this “ Amendment Agreement ”), the “ Note Agreement ”). The register for the registration and transfer of the Notes indicates that the Persons named in Annex 1 hereto (collectively, the “ Current Noteholders ”) are currently the holders of the outstanding principal amount of the Notes as set forth next to such holder’s name on Annex 1.

Capitalized terms used herein and not otherwise defined herein have the meanings ascribed to them in the Note Agreement.

Subject to Section 5, the Existing Note Agreement is amended as provided for by this Amendment Agreement in the manner specified in Exhibit A (the “ Amendment ”).

To induce you to enter into this Amendment Agreement and to consent to the Amendment, the Company represents and warrants as follows:

The Company is a corporation duly incorporated and validly existing and in good standing under the laws of the State of Delaware and has all requisite corporate power and authority to enter into and perform its obligations under this Amendment Agreement.

The execution and delivery of this Amendment Agreement by the Company and compliance by the Company with its obligations hereunder: (a) are within the corporate powers of the Company; and (b) are legal and do not conflict with, result in any breach of, constitute a default under, or result in the creation of any Lien upon any Property of the Company under the provisions of: (i) any charter instrument or bylaw to which the Company is a party or by which the Company or any of its Properties may be bound; (ii) any order, judgment, decree or ruling of any court, arbitrator or governmental authority applicable to either the Company or any of its Properties; or (iii) any agreement or instrument to which the Company is a party or by which the Company or any of its Properties may be bound or any statute or other rule or regulation of any governmental authority applicable to the Company or any of its Properties.

This Amendment Agreement has been duly authorized by all necessary action on the part of the Company, has been executed and delivered by a duly authorized officer of the Company, and constitutes a legal, valid and binding obligation of the Company, enforceable in accordance with its terms, except that enforceability may be limited by applicable bankruptcy, reorganization, arrangement, insolvency, moratorium, or other similar laws affecting the enforceability of creditors’ rights generally and subject to the availability of equitable remedies.

No event has occurred and no condition exists that, upon the execution and delivery of this Amendment Agreement, would constitute a Default or an Event of Default.

The Amendment shall become effective as of the first date written above (the “ Effective Date ”) upon:

(a) execution and delivery of a counterpart of this Amendment Agreement by the Company and by holders of 66-2/3% of aggregate outstanding principal amount of Notes;

(b) delivery by the Company of a fully executed copy of the Sharing Agreement, dated the date hereof, by and among the banks listed on the signature pages thereto, Bank of

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America, N.A., as agent, the Current Noteholders and holders of the notes issued under the 2000 Note Agreement; in form and substance satisfactory to the Current Noteholders;

(c) delivery by the Company to the Current Noteholders’ counsel of a fully executed copy of the Second Amended and Restated $175,000,000 Senior Unsecured Revolving Credit Agreement, dated as of January 11, 2006, by and among Bank of America, N.A., as administrative agent, the lenders listed on Schedule 1 attached thereto, the Company, Barnes Switzerland, Banc of America Securities LLC, as arranger, Keybank National Association, as syndication agent and HSBC Bank USA and Webster Bank, National Association, as co-documentation agents, in form and substance satisfactory to the Current Noteholders;

(d) delivery by the Company to the Current Noteholders’ counsel of a fully executed copy of an amendment, dated the date hereof to those separate Note Agreements, each dated as of November 12, 1999, (as amended by Amendment No. 1 to Note Agreement, dated as of February 5, 2003 entered into by and among 3031786 Nova Scotia Company (“ 3031786 ”) and each of the Purchasers listed on Schedule A attached thereto and by the Assumption and Amendment Agreement, dated as of August 26, 2005, by and among 3031786, the Company and each the Persons identified on Schedule A and Schedule B attached thereto, whereby the Company assumed the obligations of 3031786 under the said 1999 Note Agreement and the Nova Scotia Notes) (the “ 1999 Note Agreement ”);

(e) delivery by the Company to the Current Noteholders’ counsel of an Officer’s Certificate, dated the Effective Date, certifying that the conditions specified in Sections 4.1 and 4.2 have been fulfilled;

(f) delivery by the Company to the Current Noteholders’ counsel of a certificate of its Secretary or one of its Assistant Secretaries, dated the Effective Date, certifying as to the resolutions attached thereto and other corporate proceedings relating to the authorization, execution and delivery of this Amendment Agreement;

(g) the Company shall have paid the fees and expenses of the Current Noteholders’ special counsel and the amendment fee as provided in Section 6; and

(h) all proceedings taken in connection with this Amendment Agreement and all documents and papers relating thereto shall be satisfactory to the Current Noteholders and their counsel, and the Current Noteholders and their counsel shall have received copies of such other documents and papers as the Current Noteholders or their counsel may reasonably request in connection herewith.

6.1 Payment of Special Counsel Fees.

Whether or not the Amendment becomes effective, the Company will promptly (and in any event within thirty days of receiving any statement or invoice therefor) pay all fees, expenses and costs relating to this Amendment Agreement, including, but not limited to, the reasonable

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fees of your special counsel, Bingham McCutchen LLP, incurred in connection with the preparation, negotiation and delivery of this Amendment Agreement and any other documents related thereto. Notwithstanding the foregoing, the Company will on the Effective Date, pay the fees and expense of Bingham McCutchen LLP incurred through the Effective Date. Nothing in this Section shall limit the Company’s obligations pursuant to Section 1.5 of the Existing Note Agreement.

The Company shall have paid to each of the Current Noteholders an amendment fee in connection with the execution and delivery of this Amendment Agreement, in an amount equal to the product of (i) the aggregate outstanding principal amount of the Existing Notes held by such Current Noteholder on the Effective Date multiplied by (ii) 0.07% (7 basis points) (the “ Amendment Fee ”). The Amendment Fee shall have been paid in immediately available funds to the account or accounts of such Current Noteholder as specified below such Current Noteholders’ name in Schedule A attached hereto.

7.1. Part of Existing Note Agreement; Future References, etc.

This Amendment Agreement shall be construed in connection with and as a part of the Existing Note Agreement and, except as expressly amended by this Amendment Agreement, all terms, conditions and covenants contained in the Existing Note Agreement are hereby ratified and shall be and remain in full force and effect. Any and all notices, requests, certificates and other instruments executed and delivered after the execution and delivery of this Amendment Agreement may refer to the Existing Note Agreement without making specific reference to this Amendment Agreement, but nevertheless all such references shall include this Amendment Agreement unless the context otherwise requires.

This Amendment Agreement may be executed in any number of counterparts, each of which shall be an original but all of which together shall constitute one instrument. Each counterpart may consist of a number of copies hereof, each signed by less than all, but together signed by all, of the parties hereto. Delivery of an executed signature page by facsimile transmission or e-mail transmission of an adobe file format document (also known as a PDF file) shall be effective as delivery of a manually signed counterpart of this Amendment Agreement.

THIS AMENDMENT AGREEMENT SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH, AND THE RIGHTS OF THE PARTIES SHALL BE GOVERNED BY, THE LAW OF THE STATE OF CONNECTICUT EXCLUDING CHOICE-OF-LAW PRINCIPLES OF THE LAW OF SU