Forward and rearward seat tilt with infinite lock and free-floating back angle control Tilt tension controls the amount of resistance in the chair tilt. Lock the tilt in any position to maximize comfort. Pneumatic seat height adjusts until thighs and lower legs form a 90 degree angle. Ratchet-style back height adjusts to the most supportive position on the lower back. Seat angle can be set forward to allow proper blood flow to lower body during intensive, forward-oriented tasks. Back angle adjusts for optimum support so lumbar cushion rests comfortably against lower back. Arm height adjusts to maintain proper support of the elbow at 90 degrees. Dimensions: 26w x 25d x 41h inches