Yard Details Mayne 7831-B Mailbox Post, Black Unique new England styled product offering the timeless charm of the east coast, installs easily over a standard 4x4 wood post Our plastic mail posts are made from high quality polyethylene with built in UV inhibitors for long lasting protection from the elements Includes decorative post and mailbox support arm Small mailbox recommended. Best suited for light weight mailboxes weighing less than 7lbs, top inset panel on the post measures 1.9in w x 25.5in H 15 Year Warranty  Residential Application, 5 Year Warranty  Commercial Application.