The fitness mad 500kg studio pro swiss ball 65cm is one of the toughest balls on the market and has been sgs laboratories tasted as burst resistant at 750kg load it is also suitable for up to 500kg load and can accept a staggering static load of 17 tons without failure the ball is 65cm 256 in diameter which makes it suitable for people between 56 and 510 tall the fitness mad 500kg studio pro swiss ball 65cm is perfect for weight training fit ball workouts yoga pilates or physio