- The Universal Mounting Plate is used to mount Architectural Mailboxes on a side support arm, spreader plate, or to a 4x4 wooden post. The adapter plate is constructed of aluminum with a durable powder coat for a lasting finish.
*Additional discounts can be applied to this item. See checkout for details. Clearance, doorbusters, hot buys, overstock and temporary price cut items are not eligible for discounts.