The waterproof Plum Kegel Ball has a heavy metal shaker ball inside that encourages kegel muscles to grasp the ball strengthening the interior of your vagina and pelvic region while being extremely quiet. The structural design and supple material make it easy to insert and use. The Silicone and ABS Plum is 1.38 in. deep and 1.57 in. wide with a total length of 4.33 in., including the pull cord.