Stamford Harbor Park
333 Ludlow Street
Stamford, CT 06902 USA
tel: 203 323 9118
fax: 203 323 9119

MML CAPITAL PARTNERS LLC

June 1, 2009

The Special Committee of the Board of Directors
c/o Dean H. Blythe, Chairman
Argyle Security, Inc.
12903 Delivery Drive
San Antonio, Texas 78247

Mr. Blythe:

     We are in receipt of your letter dated May 29, 2009 and confirm that the expiration date for our offer to the board of directors of Argyle Security, Inc. dated May 19, 2009 (the “Offer Letter”) shall be extended to June 12, 2009. Except as modified by this letter, the terms and conditions of the Offer Letter remain the same.

	Very truly yours, MML Capital Partners LLC
	By:	/s/ Robert Davies
		Name:	Robert M. Davies
		Title:	Managing Director

^{LONDON                 PARIS                 FRANKFURT                  STAMFORD}