of development and rigorous testing, the DuraBall Pro Exercise Ball offers maximum firmness and support. Have confidence when you put this ultra high quality fitness ball to the test for demanding fitness workouts or weight training routines. Its perfect for larger individuals and is also suitable as a ball chair when underinflated. You can trust the DuraBall PRO Exercise Ball for superior comfort and safety with its burst-resistant rating of 1100 lb. (500 kg) and static load rating of 4400 lb. (2000 kg). Size Chart (user height) for Exercise use only: 45 cm ball = 5'2", 55 cm ball = 5'2" - 5'7", 65cm ball = 5'7" - 6'4", 75 cm ball = 6'4"+. Size Chart (user height) for Sitting & Exercise use combined: 45 cm ball = 5', 55 cm ball = 5' - 5'5", 6...  (less)