The Hanford Triple Post (With Support Brace), No Base & Lewiston Mailbox Our Hanford mailbox post system is made from rust-free cast aluminum with a durable weather resistant powder coated finish. This TRIPLE post (no decorative base) comes with support braces, three Lewiston mailboxes and mounting plate at top of post. The Lewiston mailboxes are made of cast aluminum and also feature a tough powder coat finish. Post, support braces, mailboxes, mounting plate and base color: Black. 5.00 L. 5.00 W. 73.00 H.