Task chair features a smart, flexible design that automatically adjusts to your every move. Waterfall seat edge reduces pressure for improved circulation. Enjoy custom comfort with height-adjustable padded arms. Arms adjust in height from 8-7/8" to 11-1/8" from the fabric-covered seat. Distance between arms is 17-3/4". Functions include pneumatic seat-height adjustment from 17-1/2" to 21-1/4", 360-degree swivel, tilt tension and tilt lock. Seat measures 20" wide x 16-3/4" deep. Fabric-covered back measures are 20-1/4" wide x 22-1/2" high. Five-star base has five 2" dual-wheel casters for easy chair movement.