Electric sit-to-stand desk riser adjusts up and down with the press of a button so you can easily enjoy the healthier, Sit-Stand approach to work. Adjust worksurface from 4-3/8" to 21-5/8" off your desk. Design includes stylish design, laminate top panel and keyboard tray. Aluminum base features a black powder-coat finish for durability. Electric Desk Riser with Keyboard Tray includes a single-monitor arm and bracket. Optional dual-monitor bracket is sold separately.