Nylon string, weighted Ben Wa Balls with subtle textured bumps. 4 times the pleasure. Easy climax. A woman inserts the balls and will become aroused as they move while she moves or walks around. Also builds pelvic 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. Now with subtle nubs for added stimulation and a retrieval cord for safety. Kegel exercise, Ben Wa, orgasm balls, non-vibrating sex toys. Made using ABS Plastic Balls, String Nylon. Always clean before and after use.