VITOS STABILITY BALL DOUBLE THE MATERIAL We use double the material at 1050 grams. One of the highest density exercise balls in the market and can resist up to 2200 lbs. IMPROVE FLEXIBILITY & VERSATILE USE Medium balance ball helps improve strength, agility, and balance. Hundreds of low impact exercises, can be used as office ball chair to improve your posture & relieve back pain. Pilates, yoga, back, abdominal training, and pregnancy gymnastics. NON-SLIP & ODORLESS Matte finish and horizontal lines helps with grip and avoid slipping. Professional quality with non-toxic PVC material, free of BPA & heavy metals. No plastic odor out of the box.