Heavy-Duty Ergonomic:  3 Height Adjustments in inches:  16-22, 20-28, 23-33Specialty Stools• Designed specifically for laboratoriesand medical offices• Available with 14" diameter,3" high vinyl or fabric covered seat• Pneumatic mechanism to adjust the height• Full foot ring is standard on stools except for 16 - 22 adjustable models• Casters or glides available