Standard: The "Deep Throat" cup of the Tenga masturbation cup series lets you experience a deep sucking sensation…Special valves create a virtual vacuum inside the cup, to deliver an amazing sucking sensation. The top air vent can be left open or closed, with fingertip, depending on your suction perferences. The unique pinched-in shape of the cup helps to achieve an unparalleled tightness. These advanced features combine with an arousing “slurping" sound and vibration give you the feeling that you're enjoying a real deep throat experience. Soft: The Soft cup has a softer, gentler grip for a more relaxing experience. Hard: The Hard cup provides a deep and intense suction combined with a hard tightening action. Ultra Size: The "ultrasize" and "super vacuum" (U.S.) edition cups are 20% larger and are designed for the more endowed.