Special valves create a virtual vacuum inside the cup, to deliver an amazing sucking sensation. And, the unique pinched-in shape helps to achieve an unparalleled tightness. These advanced features combine with an arousing ”slurping” sound and vibration to give you the feeling that you’re enjoying a real deep throat experience. All TENGAs have lubrication inside. The lubrication consists of: purified water, glycerin, sodium polyacrylate, phenoxy ethanol, and paraben (allergy tested in Japan). * Please note that this is product is designed to be used only once. Use condoms to extend usage.