ROUTESUN Yoga Ball Exercise Ball Gym ball, Swiss Stability Ball, Including a Free easy-to-use Foot Pump, for Labor, Physical Therapy, Fitness, yoga and Exercise sex ball (Silver grey,55 cm) Helps relax muscles, remove tension and increase tone. Increases flexibility in abdominals, thighs and lower back. Strengthens, stretches and tones all major muscle groups. Enhances coordination and balance, and improves flexibility. Tone, sculpt and chisel your shoulders, arms, thighs and abs. WHAT ARE YOU WAITING FOR?