Safco Zenergy Ball Chair helps encourage good posture and core muscle strength to help combat the negative effects of inactivity in the office. Based around an inflatable, anti-burst exercise ball, Zenergy offers the posture benefits of a yoga ball without all the inconvenient rolling around. During assembly, you can choose to install both the feet and legs on Zenergy for a seat height of 23", or just the feet for a lower seat height of 20". Weighing in at only 15 lbs., the Zenergy ball chair is easy to move from place to place and fits neatly under most work surfaces when not in use. Vinyl cover offer easy wipe-down cleaning ideal for educational environments. Part of the Safco Active Collection. Safco Active products are designed to promote active movement throughout the day and engage major muscle groups to help combat the negative effects of inactivity in the office.