STOCK PURCHASE AND CONFIDENTIALITYAGREEMENT

STOCK PURCHASE AND CONFIDENTIALITY AGREEMENT

Stock Purchase and Confidentiality Agreement (the “Agreement”), dated March 13, 2007, between and among Merrimac Industries, Inc., a Delaware corporation (the “Company”), with an address of 41 Fairfield Place, West Caldwell, MJ 07006, and Adam Smith Investment Partners, L.P., a New York limited partnership (“ASIP”), Adam Smith Capital Management LLC, a New York limited liability company (“ASCM”), Diamond Capital Management, a New York Corporation (“DCM”), Adam Smith Investments, Ltd., a British Virgin Island limited company (“ASI”), Richard Grossman (“RG”), Orin Hirschman, (“OH”) and Richard and Ana Grossman JTWROS (“RAG”), each with the address set forth on the signature pages attached hereto (each of ASIP, ASCM, DCM, ASI, RG, OH and RAG, a “Seller”, and collectively, the “Sellers”).

WHEREAS, The Sellers wish to sell to the Company, and the Company wishes to purchase from the Sellers, certain outstanding shares of common stock of the Company owned by the Sellers (such sale and purchase being referred to herein as the “Transaction”);

WHEREAS, in connection with the Transaction, the Company will disclose to the Seller certain confidential information relating to the Company’s business; and

WHEREAS, the Seller and the Company wish to set forth their understanding with respect to such confidential information.

NOW, THEREFORE, the parties agree as follows:

1. Each Seller agrees to sell to the Company, free and clear of all liens and encumbrances, and the Company agrees to purchase from each Seller, the number of shares of common stock, par value $0.01 per share, of the Company set forth next to each Seller’s name on Schedule A hereto (the “Shares”), at a price of $9.00 per share, representing an aggregate of 238,700 shares and an aggregate purchase price of $2,148,300.

2. Each Seller represents to the Company, and the Company represents and warrants to the Sellers, that it has the full right, power and authority to enter into this Agreement and to consummate the transactions contemplated hereby. Each Seller represents and warrants to the Company that it holds exclusive record and beneficial legal title to the Shares set forth next to its name on Schedule A attached hereto, free and clear of all liens, pledges, encumbrances, restrictions, and claims.

3. Confidential Information For purposes of this Agreement, “Confidential Information” means the information included in Schedule B hereto. The Sellers hereby acknowledge the receipt of the Confidential Information included in Schedule B.

4. Non-Disclosure and Trading Restrictions. Each Seller shall use the Confidential Information only in connection with the Transaction. Each Seller agrees to maintain the Confidential Information in confidence (within the meaning of Rule 100(b)(2)(ii) of Regulation FD) and to not disclose the Confidential Information to any third party without the