The Return-to-Center SwingAway Mailbox Support has a swing away design that swings out of the way of snow plows. The design allows your mailbox to swing freely 360 degrees in either direction when struck and gravity will return it to the original position. It is made of commercial grade steel and all parts are galvanized after they are manufactured to prevent rust. The support has an adjustable height to fit your needs. Fully extended, it stands 53-inches tall but can also be installed at 36-inches and 48-inches. The mailbox mounting arm is a full 48-inches allowing your mailbox to sit even further back from the edge of the roadside. It also has an internal anti-theft cable. It is easy to install with no holes to dig or cement to pour. This post is recommended by the Minnesota Department of Transportation (MNDOT) and the Federal Highway Administration (FWA) for any situation when public offices replace resident mailbox supports. It is crash-test approved. The product includes: - 4 ft. U-channel post - 1 1/4-inch galvanized pipe mailbox support that swings out of the way when impacted -48-inch mailbox mounting arm which sits further back from the road than other posts -Installation hardware NOTE: This product performs best with mailboxes under 20 lbs. Mailbox sold separately.