Mail Boss 7121, Black In-Ground Mounting Post, 43 x 4 x 4 inches, for Today, we will be discussing the Mail Boss 7121, Black In-Ground Mounting Post. This post is made of heavy-duty 10- and 14-gauge electrogalvanized steel and features a durable powder-coated finish. It can be used with a wooden post for deep in-ground installations. It includes 4 mounting bolts and clear instructions. It accepts all Mail Boss brand Locking Security Mailboxes. The Mail Boss 7121 is a great choice for those who are looking for a durable and long-lasting mailbox. The steel construction and powder-coated finish make it resistant to rust and weathering. It is also easy to install, with the included instructions and mounting bolts. The Mail Boss 7121 is a great choice for those who want a high-quality and durable mailbox.