The main advatage comparing to the reusable gun+sterile studs are: 1. Disoposable gun can avoid diseases transmitted by the reusable gun, to protect not only clients, but also operators, which is why hospitals like it. 2. To save the first investment of the piercing gun 3. Convinent, studs are preloaded. We even give a free acohol swab to disinfect the skin.