DuraBox Wall Mount Locking Deposit Drop Box Safe (W300) Secure cash, checks, small and large envelopes, suggestions, ballots, keys, and more All Steel Construction, Drop Slot Opening: 8-3/4" Width x 1/2", Capacity: 446 cubic inches Exterior Dimensions: 16-1/4" Height x 10" Width x 4" Depth, Weight: 12.2 lbs, Lock Type: Tubular Key Metal baffle inside the drop opening protects against fishing Mounting hardware for Wood and concrete is included, for indoor use