The synchronized seat and back move in harmony with the user to provide continuous comfort. Seat glide adjustment moves the seat cushion forward or back to adapt to upper leg length. Waterfall seat edge promotes better leg circulation. Height- and width-adjustable arms for upper body support. Warranted for users up to 300 lbs. The distinctive ReActiv hexagonal design is molded from flexible thermoplastic elastomers and contains dozens of intersecting nodes which flex independently and move with your body, delivering continuous support while allowing air to flow for lasting comfort.