The Ultimate Stroker is an ultimate experience. Made of a soft jelly material that warms to the body, its thrusting piston will drive all by itself for as long as you like. The butterfly tickler has 7 different vibration settings, all of which have 6 different speeds. Easy to use separate light-up multi-speed controls for vibration and thrusting. Uses 4 ?AA? Batteries, in easy to use removable battery cartridge.