Power up for bigger, thicker erections with the OptiMALE Power Pump. Watch your growth through the large, clear vacuum cylinder, featuring a soft silicone sleeve for an air-tight seal, a stylish pressure gauge, and an easy-to-read measuring guide to monitor progress. The strong auto-pump action is easily delivered with just the push of a button, and a quick-release valve button allows for customizable pressure. The Power Pump helps draw blood flow to your penis for the ultimate erection, increasing your size and sexual satisfaction. Made of phthalate-free, body-safe materials. Requires 4 AA batteries.