Product benefits Powerful erection-enhancing hydro penis pump 15% bigger than the Bathmate Hydromax 30 Accommodates penises up to 8.5 inches in length Much more comfortable than standard penis pumps Gain a bigger-than-usual erection in just 20 minutes How to use? To use, simply fill the chamber with water, place it over the penis, then compress repeatedly until a vacuum has been created. This cycle must be repeated for up to 20 minutes. By creating a vacuum chamber around the penis, the Bathmate will draw blood into the penis helping the man become aroused whilst stretching the penis so that it reaches its maximum erectile capacity. Regular use can help expand the penis & result in gains of length & girth. New design improvements in the Bathmate X30 & Bathmate X40 ensure the devices reduce pressure on the shaft of the penis & testicles, in addition to the introduction of a new valve system & clearer viewing pane. The Bathmate Hydromax X40 measures 34.5cm in length & 9.5cm in width.