Designed to encourage proper body placement, which reduces stress on the back, neck, and shoulders. Asynchronous control allows independent adjustment of back and seat angles. Positions the hips to provide proper lumbar curvature. Compound curve in the oversized seat keeps the occupant positioned against the backrest and prevents pressure on the pelvis. Waterfall-type seat eliminates pressure on the back of the thighs. Height-adjustable arms allow user to maintain 90° elbow angle.Pneumatic height adjustment: 17-1/2"23"Range of motion: seat: 7° forward/5° backward; back: 5° forward/20° backward; 4" elevationDimensions: seat: 19"W x 17-1/2"D; back: 16"W x 16"H; composite base: 25" diam.