The Hydro 7 (formerly known as the Hercules), is Bathmate's original, best-selling penis pump, with over a million sold since it was first launched in 2006. With its revolutionary design and impressive results, this easy-to-use device enables you to gain all the benefits of pumping for penile health and wellbeing. The Hydro 7 is particularly recommended for beginners as a safe and convenient way to practice penile rigidity exercises. Designed for use by men with a current penis size of 5 to 7 inches when erect. Length: 11.7 inches Canal Diameter: 2.1 inches