Desk-mounted system transforms your desk into an ergonomic sit-to-stand workstation. Pneumatic height adjustment lets you quickly switch from a seated to standing position. Large platform accommodates monitors up to 20 lb. Wide keyboard tray features a soft wrist support to place your hand in a more comfortable, ergonomic position. Adjustable clamp system securely fits virtually any size desk. Single monitor and dual monitor mounts available (sold separately). 21 1/2"W x 23 1/2"H x 23 1/2"H.