Cotytech Fully Adjustable Ergonomic Keyboard Mouse Tray-Ball Bearing-Spring (KFB-3M-BB) Composed of keyboard clamp, mouse tray (right or left hand) and wrist rest; extremely smooth movements with ball bearing mechanisms; Keyboard tray for all keyboard style; steel frame coated black; dimensions: 19.2" (L) x 5.3" - 9.4" (W) Arm tilting angles: 25 up/40 down; Keyboard platform tilting angles 19/ mouse tray rotation: 360; Loading area depth: 4.9"-7.5" (125-190mm) (distance from bottom surface of desk to this unit after being installed); Height adjustment: 5.9" (150mm) Spring mechanism enables instant height adjustments with no need of lever; Control and use your keyboard tray unit in easy ways; Meterials: solid steel & foam