Stay fit! The Perfect Core-Ball takes the guesswork out of fitness ball exercises. Our exercise ball helps to ensure optimal body positioning and maximum muscle activation by featuring a self-righting design and our exclusive Setpoint guide indicator. Stay aligned, stay safe, and stay put during your core workout with the Perfect Core-Ball. The included workout chart provides step-by-step instructions to amplify results. Beginner to advanced users. For heights 5" 4" - 5" 10". Anti-burst Includes: Perfect Core-Ball, Circuit Training Workout, air pump, plug.