PRETTY LOVE BM-010088PL The pumper handle is designed for one-handed use. Simply grip in the curve of your palm and pull up with your fingers to start the suction. An easy-to-read pressure gauge allows you to track the pressure. As soon as you're pumped to full volume, press the push-button release valve and the air will be dispersed safely and easily. The vacuum cylinder is made with clear, safety-ensured plastic with ruler markings on it so you can see just how much your penis has grown.