Electric Desk Riser with keyboard tray adjusts up & down with the push of a button. Height ranges from 5-1/4" to 17-1/8" off your worksurface. Medical-grade electric motor provides a quick-release, low-noise operation. Anti-collision function will stop the up / down motion if desk riser meets objects like coffee cups or bottles. The top surface (31-1/2" wide x 24-2/5") includes USB interface for convenient connection & holds monitors up to 33 lb. The 24-1/4" wide x 8-2/3" deep keyboard tray is large enough for a keyboard & mouse.