The BetterPosture Kneeling Chair - Standard, model F1420, is a height-adjustable posture chair designed to promote good posture and strengthen the lower back muscles. The user sits in a kneeling posture with the knees resting on a knee pad. This manually height adjustable kneeling chair has a steel frame with nylon casters. The seat and knee pad are made of supportive polyurethane foam covered with durable fabric. DIMENSIONS (HxLxW): 21 to 28.5 x 29 x 18 inches. The seat is 12.5 x 17.5 inches. The knee cushion is 6.5 x 11 inches. CAPACITY: 280 pounds. WEIGHT: 17 pounds. COLOR: Black. WARRANTY: Five years.