Loan Agreement

Exhibit 10.3 December 16, 2008 MasTec, Inc. and the other
Borrowers referred to below
800 Douglas Road, North Tower, 12th Floor
Coral Gables, Florida 33134
Attention: Chief Executive Officer
  Ladies and Gentlemen:      We refer to the Second Amended and Restated Loan and Security Agreement dated July 29, 2008 (as at any time amended, restated, modified or supplemented, the "Loan Agreement"), by and among MasTec, Inc., a Florida corporation ("MasTec"), certain of the Subsidiaries of MasTec which are identified on the signature pages hereto (together with MasTec, collectively, "Borrowers"), the financial institutions party thereto from time to time (the "Lenders") and Bank of America, N.A., as administrative agent for the Lenders (the "Agent"). All capitalized terms used in this letter agreement, unless otherwise defined herein, shall have the meaning ascribed to such terms in the Loan Agreement.      Borrowers have advised the Agent and the Lenders that MasTec North America, Inc., a Florida corporation ("MasTec North America"), has entered into a Stock Purchase Agreement dated as of October 4, 2008, as amended by that certain First Amendment to Stock Purchase Agreement dated as of December 2, 2008, and that certain Second Amendment to Stock Purchase Agreement dated as of December 13, 2008 (the "Purchase Agreement"), with Wanzek Construction, Inc., a North Dakota corporation ("Wanzek"), Trust B under the Amended and Restated Living Trust of Leo Wanzek dated February 2, 2000, a North Dakota trust ("Wanzek QTIP"), Janet L. Wanzek, a North Dakota resident ("Janet Wanzek"), Wanzek Construction 2008 Irrevocable Trust, a North Dakota trust ("Wanzek IDIT"), Jon L. Wanzek, a North Dakota resident ("Jon Wanzek"), and Jon L. Wanzek 2008 Two-Year Irrevocable Annuity Trust, a North Dakota trust ("Wanzek GRAT"; Wanzek QTIP, Janet Wanzek, Wanzek IDIT, Jon Wanzek, and Wanzek GRAT are collectively referred to herein as "Sellers" and individually as "Seller"), and Jon Wanzek in his capacity as Sellers’ Representative ("Sellers’ Representative") pursuant to which MasTec North America proposes to purchase from Sellers and Sellers propose to sell to MasTec North America all of the issued and outstanding capital stock of Wanzek (the "Wanzek Stock"). The foregoing transaction is hereinafter referred to as the "Wanzek Acquisition".      Borrowers acknowledge that pursuant to Section 10.2.13 of the Loan Agreement, Borrowers may not consummate the Wanzek Acquisition unless such Acquisition constitutes a Permitted Acquisition under the Loan Agreement. Borrowers have represented to the Agent and the Lenders that, with the exception of the amount of the Purchase Price, the Wanzek Acquisition will constitute a Permitted Acquisition under the Loan Agreement and have requested, notwithstanding the fact that the Purchase Price of the Wanzek Acquisition exceeds the amount permitted under the Loan Agreement, that the Agent and the Lenders acknowledge and consent to the Wanzek Acquisition as a Permitted Acquisition under the Loan Agreement.      The Agent and the Lenders are willing to acknowledge and consent to the Wanzek Acquisition as a Permitted Acquisition, subject to the terms and conditions set forth herein.      The parties also desire to amend the Loan Agreement, subject to the terms and conditions set forth herein.      NOW, THEREFORE, for the sum of TEN DOLLARS ($10.00) in hand paid and other good and valuable consideration, the receipt and sufficiency of which are hereby severally acknowledged, the parties hereto, intending to be legally bound hereby, agree as follows:

      1.  Acknowledgment of and Consent to Wanzek Acquisition as a Permitted Acquisition . At the request of Borrowers, the Agent and the Lenders hereby acknowledge and consent to the Wanzek Acquisition as a Permitted Acquisition, so long as the following conditions have been satisfied in form and substance satisfactory to the Agent on the date of the closing of the Wanzek Acquisition (which closing date shall be no later than January 2, 2009): (i) Borrowers shall have satisfied all of the conditions to a Permitted Acquisition set forth in the Loan Agreement other than the Purchase Price requirement set forth in clause (c) of the definition of "Permitted Acquisition"; (ii) The Purchase Price of the Wanzek Acquisition does not exceed $182,475,000 (excluding any earn-out payments due Sellers after the date hereof), which Purchase Price shall consist of (A) $50,000,000 in cash, (B) $62,475,000 in Equity Interests of MasTec (subject to fluctuations in value based on market conditions), (C) the assumption by MasTec of $15,000,000 of indebtedness owing by Wanzek, and (D) the incurrence of Subordinated Debt in the principal amount of $55,000,000; and (iii) Borrowers shall have delivered to the Agent a duly executed Certificate Regarding Permitted Acquisition, in the form attached as Exhibit A hereto, together with all attachments thereto and other documents referenced therein and required to be delivered in connection therewith.       2.  Amendments to Loan Agreement . The Loan Agreement is hereby amended as follows:      (a) By deleting the first paragraph of the definition of "Applicable Margin" contained in Section 1.1 of the Loan Agreement and the pricing grid set forth immediately thereafter, and by substituting in lieu thereof the following:       Applicable Margin — a percentage equal to 1.25% with respect to Revolver Loans that are Base Rate Loans and 2.50% with respect to Revolver Loans that are LIBOR Loans; provided , that commencing on the first day of the calendar month immediately succeeding the third Business Day (each an "Adjustment Date") after Agent’s receipt of the applicable financial statements and corresponding Compliance Certificate for each Fiscal Quarter ending on or after June 30, 2009, the Applicable Margin shall be increased or (if no Default or Event of Default exists) decreased, on a quarterly basis according to the performance of Borrowers as measured by the Leverage Ratio for the immediately preceding Fiscal Quarter of Borrowers, as follows:

     (b) By deleting the definitions of "Base Rate" and "Federal Funds Rate" contained in Section 1.1 of the Loan Agreement, and by substituting in lieu thereof the following new definitions, in proper alphabetical sequence:       Base Rate — for any day, a per annum rate equal to the greater of (a) the Prime Rate for such day; (b) the Federal Funds Rate for such day, plus 0.50%; or (c) Adjusted LIBOR Rate for a 30 day interest period as determined on such day, plus 1.00%.       Federal Funds Rate — (a) the weighted average of interest rates on overnight federal funds transactions with members of the Federal Reserve System arranged by federal funds brokers on the applicable Business Day (or on the preceding Business Day, if the applicable day is not a Business Day), as published by the Federal Reserve Bank of New York on the next Business Day; or (b) if no such rate is published on the next Business Day, the average rate (rounded up, if necessary, to the nearest 1/8 of 1%) charged to BofA on the applicable day on such transactions, as determined by Agent.      (c) By adding the following new definitions of "Defaulting Lender", "Prime Rate" and "Wanzek Sellers" to Section 1.1 of the Loan Agreement, in proper alphabetical sequence:       Defaulting Lender — any Lender that (a) fails to make any payment or provide funds to Agent or any Borrower as required hereunder or is in breach of or fails otherwise to perform its obligations under any Loan Document, and such failure is not cured within one Business Day, or (b) is the subject of any Insolvency Proceeding.       Prime Rate — the rate of interest announced by BofA from time to time as its prime rate. Such rate is set by BofA on the basis of various factors, including its costs and desired return, general economic conditions and other factors, and is used as a reference point for pricing some loans, which may be priced at, above or below such rate. Any change in such rate announced by BofA shall take effect at the opening of business on the day specified in the public announcement of such change.       Wanzek Sellers — shall have the meaning ascribed to "Sellers" in that certain Stock Purchase Agreement dated as of October 4, 2008, as at any time amended, modified, restated or supplemented, among MasTec, MasTec North America, Wanzek Construction, Inc., a North Dakota corporation, Trust B under the Amended and Restated Living Trust of Leo Wanzek dated February 2, 2000, a North Dakota trust, Janet L. Wanzek, a North Dakota resident, Wanzek Construction 2008 Irrevocable Trust, a North Dakota trust, Jon L. Wanzek, a North Dakota resident, and Jon L. Wanzek 2008 Two-Year Irrevocable Annuity Trust, a North Dakota trust, and Jon Wanzek in his capacity as sellers’ representative.

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     (d) By adding a new subclause (z) to Section 2.3.1(i) of the Loan Agreement, so that Section 2.3.1(i) of the Loan Agreement reads in its entirety as follows:      (i) Each Borrower acknowledges that Issuing Bank’s willingness to issue any Letter of Credit is conditioned upon Issuing Bank’s receipt of (A) an LC Application with respect to the requested Letter of Credit and (B) such other instruments and agreements as Issuing Bank may customarily require for the issuance of a letter of credit of equivalent type and amount as the requested L