Gymnic Exercise Balls are your trusted source for exercise safety. In a lab test, an initial load of 200 lbs was slowly lowered onto the ball, then stabilized for 5 minutes. An additional 100 lbs was added every 60 seconds. All samples withstood 3,000 lbs without rupture or loss of pressure. This item is shipped deflated and needs to be blown up with a needle pump(Not included). The gymnic classic balls provide the movement kids crave while also getting exercise. This is a great item for individuals with Autism and SPD who are in constant motion. The balls are made of Ledraplastic and are pthalathes free.