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Exhibit 10.4.12

March 28, 2007

Attention: Jane Todd

Dear Sirs/Mesdames:

Reference is made to a Loan Agreement dated as of June 1, 2004 as amended March 10, 2005, August 17, 2005, June 12, 2006, August 1, 2006 and September 20, 2006 (the “Loan Agreement”) between SMTC Manufacturing Corporation of California, SMTC Manufacturing Corporation of Wisconsin, SMTC Manufacturing Corporation of Massachusetts and SMTC Mex Holdings, Inc., as borrowers (“Borrowers”), and Congress Financial Corporation (Central), now known as Wachovia Capital Finance Corporation (Central), as lender (“Lender”). All capitalized terms used in this notice of extension but not defined herein have the meanings given to such terms in the Loan Agreement.

Borrowers are hereby given notice that Lender has agreed to extend the Renewal Date of the Loan Agreement to April 15, 2008. All other terms and conditions of the Loan Agreement remain in full force and effect, unamended. Borrowers agree to pay to Lender an early termination fee equal to 0.50% of the US Maximum Credit if the Loan Agreement is terminated prior to October 15, 2007.

The undersigned Borrowers hereby acknowledge receipt of the foregoing notice of extension of the Loan Agreement and agree to same.

Dated this 28^th day of March, 2007.

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Echo f the undersigned Obligors hereby:

Dated this 28^th day of March, 2007.

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