Gaines Manufacturing Black with Polished Brass Mailbox KS-7A Original Keystone Cast Alum Mailbox KS-7A Mailbox Measures 12  H x 10 3/8Wx 20 1/8 D Solid Brass Door Keystone Mailbox Collections are die cast from aerospace-grade, rust-proof aluminum. They are finished with a highly protective state-of-the-art five step powder coated paint process