Large Balls Silver. Large double weighted balls on a washable nylon cord. A woman inserts the balls and will become aroused as they move while she moves or walks around. Also builds muscle strength. The balls are weighted so that you have to contract your muscles to hold them in. This is not only helpful with strengthening vaginal muscles but also helps strengthen bladder control. Great for Kegel exercises. Non-vibrating ben wa style balls move by kinetic energy. Always clean before and after use. Large Balls from Nasstoys of New York.