When this soft silicone sleeve is put onto this 7? hard plastic vibrator, you get the best of both worlds, a firm hard vibrator yet soft and giving that only silicone can provide. The penis shaped sleeve is made of a stretchable silicon, making it easy to put on or remove and making it even easier to keep hygienically clean. Easy to use multi-speed controls at your fingertips. Uses 2 ?AA? batteries.