Architectural Mailboxes Oasis Drop Box Black Body constructed of heavy 16 and 14 gauge galvanized steel for durability and long life Commercial grade powder coated finish Use Universal Adapter Plate 5530 for 4x4 wood post installation Can be installed atop or into a masonry column 18.5-Inch d x 20-Inch h x 13.5-Inch w, 41-Pound