Self Skin Ergonomic Laboratory Chair with Seat and Back Tilt and Black Composite Base Standard Height 21" to 31" Base Diameter 24" Seat Dimension 18"W x 18"D Overall Height with Backrest 36" to 46" Foot Ring Diameter 20" Back Dimension 16"W x 12"H Urethane Seat and Back Adjustable Back Rest Height Only Pneumatic Height Adjustment Available in Black Only Weight Capacity 300 lbs 841 Options 7" Stroke Cylinder: 19" - 26" (Order Ex. 841-7) Soft Wheel Casters or Glides (Please Specify)