Vaginal cylinder is hand crafted of industrial strength crystal clear acrylics. Through a strong vacuum. the cylinder can increase the amount of blood in the vaginal area. Tapered toward the top to match the natural shape and for maximum comfort. Includes a quick connect/disconnect safety valve that maintains the vacuum after you disconnect the pump. Large size (4.25 in. by 5.25 in.) Does not include a hand pump or hose. sold separately.