The Handy Post Double sleeve (mailboxes not included) is constructed of maintenance-free and durable PVC (Vinyl) and comes with a Lifetime Warranty against peeling, flaking, blistering, corroding, rotting and manufacturing defects. It is designed to fit over an existing or new wood 4x4 (actual 3.5"x3.5") post, or can fit over many no-dig supports of similar dimensions. If your mailboxes are secured to any type of wood 4x4 configuration, you can modify it by cutting it to a straight up 52" height or less to accept The Handy Post Double. The Handy Post Double is designed to accommodate two different mailboxes on one post. Each arm extends 13.5" from the vertical upright and will accommodate up to 50lbs with no sag. This aesthetically pleasing, economical product will enhance any home, business or neighborhood property. The Handy Post Double will add character to any setting. Conveniently packaged with stainless steel hardware and installation instructions included.