Sit-to-Standing Desk Riser's large work space measures 40" wide x 23.6" deep, holds up to 40 lb. and lets you work from a seated or standing position. Benefits of alternating between sitting and standing while working include reduced back pain and strain and a boost in overall health and energy. Large, retractable keyboard tray offers additional storage space at an ergonomic position 4.5" below the desktop. Desk riser adjusts to heights ranging from 5" to 20" and creates an ergonomic work space for persons of most heights. Straight up-and-down motion allows a minimized required depth. Conveniently placed grommet hole provides hassle-free cable/wire management.