Pump up your penis for a stronger. bigger. and more sensitive erection! This penis pump is easy-to-use with results that will keep you cumming back for more. Slide into the silicone sleeve using a little water-based lube for sleekness. The tight opening will create a seal around your penis so that pressure can build within. The cylinder is textured for a firm grasp. clear so that you can watch yourself grow. and marked with measurements so that you can track your progress! The trigger handle pump is easy to use - just squeeze to build begin the suction process. When you are ready to tap out. press the air-release valve on the flexible hose to quickly reduce pressure within the cylinder. Measurements: Cylinder is 8.5 inches insertable length. 2.35 inches in diameter. Silicone opening is .75 inches in diameter. unstretched. Hose is 8.75 inches in length.