http://www.moonyblue.com/2-meter-water-walking-roll-ball-inflatable-zorb-ball?___store=us

http://www.moonyblue.com/2-meter-water-walking-roll-ball-inflatable-zorb-ball?___store=us

The water balls, dance balls have enough breathable air volume inside the sphere for a normal person to remain inside for a long time without the need to refill the ball with fresh air. Made with PVC.