This Silicone Cylinder Cushion is designed specifically for our penis cylinders, made to cushion the bottom of the cylinders while pumping, and provides the best seal while pumping at any pressure. It will not change the inner diameter of your cylinder. This item works especially well for men with heavy public hairs who do not want to trim the area for pumping. Made of high quality, medical grade silicone. Package Weight 2.40 Ounces Package Dimensions 3.50W by 3.50H by 1.00L inches