The Stanley Works, New Britain, Conn., announced an agreement to purchase 100 percent of the shares of Sonitrol Corporation from an ownership group comprised of Carlyle Venture Partners, Wachovia Capital Partners and Spire Capital Partners, as well as selected members of Sonitrol management for $275 million cash.

Sonitrol, headquartered in Berwyn, Pa., provides security monitoring services, access control and fire detection systems to commercial customers in North America via two monitoring centers and a national multi-channel distribution network. Ranked No. 8 on the SDM 100, Sonitrol brings a strong brand, capabilities in audio-verified monitoring and a substantial national account base to Stanley’s Convergent Security Solutions platform. Sonitrol, with revenue totaling approximately $110 million will report into Stanley’s Convergent Security Solutions business, which had 2007 revenues approaching $600 million.

Stanley also purchased the retail branch business of National Guardian Security Services Inc., Norwalk, Conn. The purchase includes both commercial and residential accounts across the United States with strong concentration in California, Missouri and Kansas. Terms of the sale were not disclosed.

“The acquisition of these accounts from National Guardian continues our commitment to growing our electronic security platform domestically in the United States,” stated Brett Bontrager, president, Stanley CSS.

George Flagg, chief executive officer of National Guardian, said, “Providing outstanding service to customers has been the focus of every company I have operated. Having Stanley Convergent Security Solutions acquire these key accounts assures me and our customers that they will receive the best on-going service and responsiveness in the alarm industry.”