Flex Chair features a soft plastic back that can curve freely when people recline to create a very comfortable lumbar and back support. Plastic back is vented for breathability. Height-adjustable arms have soft polyurethane pads for added comfort. Other functions include pneumatic seat-height adjustment, 360-degree swivel, tilt, tilt lock and tension. Five-star nylon base is equipped with casters for easy chair movement. Weight capacity is 250 lb.