A prostate plug is a male anal toy and is used to stimulate the prostate. For this reason, this type of sex toy is also called a prostate stimulator . A prostate stimulator can be recognized by its spherical head and a curvature in the shaft . In addition, they have a wide end, so that the toys cannot shoot in during use. The curved shaft ensures that the plug moves towards the prostate during insertion. The bulbous head is used to rub against the prostate from the inside. A number of prostate stimulators from this category also have the ability to deliver vibrations .