With its hourglass shape and special valves. the Original Vacuum CUP delivers amazing suction and stimulation from unique internal details. To create a strong internal vacuum. simply remove the sticker at the top of the cup before use and cover with your finger while using. Cup features the smooth pad insertion mechanism! This mechanism not only offers extra adherence. air-tightness and less lubricant leakage. but will automatically apply lubricant to your shaft as you insert! Cup Measurements: 2.7 inches wide and 6.1 inches tall Note: One-Time Use Recommended.