If your penis is larger than average, the Hydromax X40 is designed to give it an extra boost. The X40 hydrotherapy penis pump uses water instead of air for better results and offers 35% more power than it’s predecessor, the Hercules. This penis pump can be used in the bath or the shower for easy incorporation into your regular routine. This pump fits men with an erect penis length of 18-23cm and an erect girth of 5.5 cm. It’s 15% bigger than the X30 and has extra features like a Super Flow Valve System for single-handed use as well as a Swivel Bellows feature for 360 degree rotation.