Penis pumps are built to either add length and girth to the penis, or to achieve and maintain an erection. The best penis pumps come with two basic pumping styles, the bulb pump and the hand pump. Each type of penis pump creates a vacuum in the chamber which then draws blood to the penis making it larger. Penis pump users usually report an increase in their length or girth after regular penis pump usage. While a not a traditional male sex toy, many men use penis pumps as a form of masturbation.