A penis enlargement pump is simply a mechanical device that creates a vacuum to draw blood into your penis. Think of it as a very low suction vacuum cleaner. A device used to enlarge the penis. Pumping the handle will remove air to create a vacuum in the pump. This will only enlarge your penis temporarily. If used. Bathmate Hydromax the most advanced penis developer in the world, buy online now! full lineup. We have a Hydropump perfect for your size and experience.