Visit our Service Center. Let us provide you with the best security. 9140 Gaither Rd. Gaithersburg, Maryland 20877 Phone: 301-948-1996 Toll Free out of area: 1-800-772-9811Fax: 301-948-5265 Email: hhlock@erols.com Hours: Monday through Saturday 8:00AM to 5:00PM Sunday Closed Home Our Services Our Pr...