Ideal for apartments, condominiums, commercial buildings and many other applications . Includes factory installed commercial lock . Fit into a rough opening 13.75 in. W x 17.75 in. H x 6.75 in. D . Secured with mounting hardware not included through the back or side panels . Fully integrated flanged collar fits over the rough opening . Made of extruded Aluminum. 11.5 in. W x 0.75 in. H mail slot . Comes standard with lock and keys for each individual mailbox. Does not include master lock for U.S.P.S. entry; must be provided by U.S.P.S. . 15 in. W x 6.75 in. D x 19 in. H (20?lbs.)