The PDX ELITE® Suck-N-Pump Stroker features a medical-style pump ball that functions as an erection pump in one position and as a masturbator in a second position – twice the performance options of a regular pump! Penis Pump - With each squeeze of the medical style pump ball into the pump position, a super strong vacuum is created within the chamber, forcing your erection to rapidly expand in length and girth. Stroker Masturbator - When the pump ball is placed in the masturbator position, your shaft is surrounded by a super tight oral sex suction. Turn the top dial to activate powerful multi-speed vibrations for extra stimulation. The soft TPR sleeve forms a tight seal against your skin, creating incredible suction and amazing results, while the clear tube is designed for a firm grip and has a convenient ruler to measure your expansive growth. You can instantly relieve pressure by pressing the air release valve on the pump cylinder. • Powerful vibration • Transparent cylinder with ruler coating • Stimulating sleeve • Hermetic seal • Waterproof Penis Pump: Place the ball end of the pump that says "Pump" onto the end of the flexible tube. Electronic Masturbator: Place the ball end of the pump marked "stroker" onto the end of the flexible tube. Press the quick-release button to instantly relieve pressure. To prolong ejaculation, slide one of the included silicone C-rings over your penis until it's snug. The firm pressure will help maintain your erection and prolong the fun.