The fitness mad 300kg anti burst swiss ball 55cm is designed to help you improve balance muscle tone and flexibility as well as to strengthen the core muscles this lightweight and durable ball is suitable for fit ball workouts yoga pilates and physiotherapy and can be used as a chair to aid with postural problems the ball is rated as suitable for 300kg 6614lbs load and has been sgs labs tested as burst resistant at over 500kg 11023lbs static load it is 55cm 217 in diameter whic