Challenge torso stability and improve balance. The anti-burst STOTT PILATES* Stability Ball Plus has non-slip polyvinyl ribbed surface. Can be used to simulate Reformer-style exercises. Tested under 250kg pressure. Includes pump. Available in three sizes: 55cm Ball (blue) recommended for those 5'7" and under. 65cm Ball (green) recommended for those 5'8" - 6'. 75cm Ball (purple) recommend for those 6' and over.