Enhancement Kit Pro Tension Sex Toys for men How Does Penis Extender Work? 1 Imagine a weight trainer lifting a weight. As he does so, with progressively heavier weights, he stretches and trains the muscles he is lifting with. This causes small micro tears and cell duplications to occur along the muscle. As the muscle heals, it becomes larger, firmer and holds more blood as it gets bigger. Penis traction device work in a similar way. 2 By simply attaching our Penis Extender to your penis, it supplies a steady, constant and gentle stretch along the Corpora Cavernosa (the part of the penis that holds blood during erections).