The Handy Post 4L 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 4 x 4 (actual 3.5 in. x 3.5 in.) post, or can fit over many no-dig supports of similar dimensions. If your mailboxes are secured to any type of wood 4 x 4 configuration, you can modify it by cutting it to a straight up 42 in. H or less to accept The Handy Post 4L. The Handy Post 4L is designed to Accommodate four (4) different mailboxes (maximum width 8.7 in. each) on 1 post. The arm is 45 in. across the vertical upright and will Accommodate up to 200 lbs. with no sag. This aesthetically pleasing, economical product will enhance any housing, business or neighborhood property. The Handy Post 4L will add character to any setting. Conveniently packaged with stainless steel hardware and installation instructions included.