Kegel balls are used to strengthen your Kegels. This easy to use system has 4 weights to customize your work out. 1 blue 15g, 1 red 25g, 1 purple 35g and 1 grey 55g. The kit comes with a sleeves for for you to change the weighted balls as you progress. Stronger Kegels lead to better control of your pelvic floor, stronger orgasms and better bladder control. Waterproof and made from a body safe silicone.