Masturbation pump is easy to use providing incredible suction. Features include automatic pressure control suto start/stop and quick air release button. Flanged base for a secure seal and a body-safe donut. Includes ergonomic hand-held controller with push button controls and an easy-to-read LED display measures PSI vacuum inside the compact cylinder. Requires 4 AAA batteries not included. Cylinder measures 4 in. by 2 in.