The Bathmate Hydromax is the world's best selling penis pump with 1 million units sold to date. Available in over 90 countries, this provides the ultimate in hydro-technology for your penis. The range of three sizes X20, X30 and X40 cover the size of every man. The Hydromax series is the next stage of Hydro-pump evolution. The new bellows pump system and valve give 35% more power than the original Hercules.