Fellowes 8036001 Professional Premier Series Adjustable Keyboard Tray, 19w x 10-5/8d, Black Comfort-Lift system lets you slide mouse platform left or right over keyboard numeric pad and offers 2 custom height positions Mouse platform tilts forward or backward and adjusts up or down to height of keyboard Mouse platform mounts on left or right side of keyboard Warning Trak helps prevent mouse from sliding off mousing platform Lift and lock feature lets you adjust height with one hand