This triple set of ben wa balls are dual layered for exciting internal movement. With each shift, the inner ball rolls within the outer ball, causing subtle vibrations. Versatile and simple, this timeless design has been delighting men and women alike for centuries. With no batteries to replace or vibrating motor, you can enjoy the benefits of increased tightness and sensitivity with regular use, all in complete silence and with ultimate discretion. The balls are tethered together with a simple nylon cord, featuring a loop at the end for easy retrieval. The comfortable and slick ABS plastic inserts easily and can be worn all day.