Whether you use our exercise gym ball as an alternative seat or a training tool, it will help improve posture and strength. It also helps increase the body's flexibility and balance. Designed for commercial use, our gym balls are made from a robust anti-burst latex rubber that have a weight capacity of 500kg. Our gym ball includes exercise chart, ball pump and tape measure. This is definitely a great addition to any home gym's list of must-have equipment. Choose the right size for your height, or ask as to recommend which ball is right for you. A general guide is below 45cm - Yellow - Less than 5ft Tall 55cm - Red - 5ft - 5ft 7inch Tall 65cm - Green - 5ft 8inch - 6ft Tall 75cm - Blue - More than 6ft+