Features:Size:diameter is 80mm*33mm/3.15 inch * 1.30 inch,the aperture diameter is 19mm/0.75 inch.(Pls Note about the Size)Material:Medical Level SiliconeColor: Black,ClearNote: Cylinder not includedThe gum cover of Electric Pump (silicone seal )Silicone sleeve that adds a smoother, more pleasurable feel to your pumping sessionHelps sustain your when used like a constriction ring after pumping!Included 1Pcs Silicone Sealing Donut Sleeves Note:We suggest you use a gentle antibacterial soap and water wash it before use and let air dry or wipe down with a soft cloth