Use for Humanscale standard keyboard tray/track. Is installed at the end to prevent keyboard tray from sliding off the track. Brand New, great replacement part, OEM Humanscal part. Includes: 1- Humanscale end cap (5 1/2 inches long) 2 - Twist caps to secure end cap 2 - Adhesive wire straps 12 - Black screws for mounting tray Ships quickly from CA!