Custom and tested by lots of tattoo artists on human. Needles made by 304 L, polished by automatic machine that working more smooth.? Consummate colored texture makes your joyful feeling of Sculpture. Complete Ethylene oxide disinfection, disposable single use. Strict quality and consistency control, Smooth and free of impurities. Every detail of shell makes extreme comfort. A Perfectly matches with needles and shell, high-stability, smooth unhindered ink flow. Advanced visual optimization tube, key-head shape of the shell side, to the tip, right angels at all four sides, reduce the distortion and refraction of spherical lens. 4 thickened bars ensured the high strength of durability, close to 200 rebound force with toughness.