Use the IBF Iron Body Fitness Pro Series fitness ball to perform a range of exercises to build muscle strength, and improve your flexibility, balance, and coordination. Replace your chair with the ball for a passive workout that improves your posture and tones your body. Its anti-burst design ensures the ball won't burst if punctured, instead, it will deflate slowly. Inflate and deflate with the included pump. Available in 55, 65, and 75 cm sizes.