HON 4028P Underdesk Oversized Keyboard Platform/Mouse Tray, 30 x 10, Black Designed to place your keyboard and mouse pad in the most comfortable, convenient position Keyboard can be installed at one of four pre-set heights to improve wrist and forearm alignment Platform surface is positioned 3" below bottom of worksurface The non-articulating platform glides smoothly on steel, ball-bearing suspensions Sturdy reinforced steel construction adds strength and durability