The Blickman 8867SS (Benjamin) foot-operated Mayo Stands are number one in ease and convenience. Just lift the tray frame - it automatically locks. To lower, hold the tray frame and press the foot operated control button. Release to lock in place. A guard over the foot button prevents accidental release. Our Blickman state-of-the-art double post design minimizes lateral movement and increases overall unit stability. Select our Model 8871SS, double-post jumbo Benjamin Mayo Stand when a larger tray size is required. The height adjustment of the 8867SS is 39-1/2 to 62" and the tray size is 12-5/8" x 19-1/8".