Core workout, abdominal, thigh, leg and arm toning. Strengthens posture and mobility. One of the best upper thigh exercises for women due to the resistance it places on the inner and outer thighs. Improves muscle tone of the upper inner and outer thighs, arms, lower body, upper body and core. 14 inch diameter with non-slip foam padded grips. Tone your arms, thighs and chest.