Self-Locking Security Mailbox $39.95 (plus $14.50 shipping) Measures: 21" L x 10 3/4" H x 8 1/4" W Lockable, includes lock and two keys. Unique patented self-locking door permits mail deliveries without a key. No mail slots: full door access for the delivery of large and bulky packages. 81% larger than standard sized mailboxes. Made of ribbed galvanized steel Quantity: We gladly accept Copyright 2004. All Rights Reserved. Web site design by Morganic Studios.