Mounted through a masonry wall or fence, mail is delivered through the front flap and retrieved from the rear lockable secure access door. Mailbox is made from solid aluminum, is totally waterproof and has a quality black enamel finish. It features a large capacity secure mail storage area with lockable rear retrieval door which is supplied with 2 keys. Rear access door opening: W 7″ x H 7.5″ Incoming opening: W 9″ x H 2.5″ Weight: 15 lbs.