The Silicone Universal Pump Sleeve is soft and an incredibly comfortable donut which cushions your penis whilst pumping. Effective pumping best works when creating an airtight firm seal around the base shaft of your penis. Increased pressure promotes blood flow to your penis to help achieve results when pumping. The airtight seal results in harder firmer erections. The Universal Silicone Pump Sleeve helps to create a more relaxed and enjoyable pumping experience.