The Mail Boss Mail Manager Curbside Locking Mailbox comes with 3 keys and hardware for installation.The package bin design allows you to accept mail bundles and small packages. Features a patented anti-pry latch locking mechanism to prevent leveraged entry. and mail manager locking security. 11.25" x 10.75" x 21". Can also be mounted on a 4x4 wood post. Includes four lag bolts for easy mounting.