Black Polyurethane Ray Sit-Stand Desk Height Stool is adjustable from 16.5-21.5 inches from the top of the seat to the floor and features ergonomic adjustments such as seat height and locking seat tilt and black, nylon-reinforced fiberglass base with dual-wheel, self-braking, non-marring casters suitable for hard floors in chemical, soil, and puncture resistant polyurethane.