The Cock Rocker is made from unscented Silicone. Receive sturdy support and enhancement while both of you enjoy erotic vibrations from above and below. You will both take pleasure in the dual stimulators for foreplay and lovemaking. The removable water proof micro size stimulators activate with the push of a button. Each vibrating bullet requires 4 watch size batteries. Sixteen batteries are included to keep the satisfaction buzzing. One size fits most. This ultimate cock ring is power packed!