Professional chair features built-in lumbar support, arms that adjust in height and width and a VeraFlex breathable fabric back with matching VeraFlex fabric seat. Functions include one-touch pneumatic seat-height adjustment, synchronized knee tilt and integral lumbar. Heavy-duty nylon, five-star base has oversized dual-wheel casters. Seat size is 20" wide x 20" deep x 3-1/4" high. Back measures 20" wide x 20-1/2". Distance between arms is 18-1/4".