High Back Manager Chair features pneumatic seat height adjustment from 16" to 21", swivel/tilt mechanism that provides 360º movement and a tension knob and tilt lock that allow user to adjust resistance when rocking forward or back. 5-star nylon base is 24" dia. and nylon carpet casters. Chair measures 24"Dia. x 35-1/2 to 39-1/2"H overall. Meets or exceeds ANSI/BIFMA standards. Black powder coat finish frame. Some assembly required.