This penis pump is ideal for beginners who want to increase the size of their cock. The device creates a tight vacuum seal around the penis, causing intense suction and additional mass. The pump has a quick air release control, pneumatic bulb, latex ring for a tight seal and a see-thru cylinder to monitor the results. Step-By-Step Instructions Measurements: The cylinder is approximately 9 inches in length, the circumferences is 7.5 inches at its widest point and the opening is approximately 2.5 inches in diameter. The hose measures 14.5 inches long.