Adjustable keyboard arm accommodates a wide range of computer users. Ergonomic design lifts, lowers and tilts your keyboard for optimum comfort. Keyboard arm extends and retracts from under your worksurface. Flexible installation methods allow you to either clamp it to the front edge of your desk or attach with four screws under your desk's surface. Ball-bearing slides produce smooth motion. Keyboard arm meets ANSI/BIFMA X5.5-2008 requirements.