Used to improve balance, coordination, flexibility, and strength, and even just for fun. Used by pediatric and NDT therapists as aids for vestibular movement, in equilibrium therapy by fitness professionals as aids for stretching and strength programs, as seats, and even by pregnant women in birthing classes. The Cando® balls have a nonslip PVC vinyl surface that is ribbed for extra security. They may be underinflated to give a soft, mushy feel or overinflated for a firm, bouncy feel. They can support up to 600 lb (275 kg).