Many people use their exercise ball at a desk instead of a chair. Active Sitting promotes core muscle use which can strengthen the back, help prevent fatigue and improve posture. But there’s nothing more annoying than having your ball roll away when you stand up. Now you can stop chasing your ball around the office—with the NEW Ball Holder. This inflatable ring holds one 65cm-75cm exercise ball and keeps the ball from rolling away when not in use. Ball sold separately.