EZ Revolution Needles with membrane: new generation of EZ cartridge needles with inner membrane, a security system that does not allow the ink to pass inside the grip or the tattoo machine. The cartridge housing is made with medical grade plastic and the needles with 316L surgical steel. Individually packed and sterilized with EO gas (ethylene oxide). Easy to use and exchange: just remove the needle, discard it, insert the new cartridge and you're done. Each needle has a spring system that allows the amount of liquid to be consistent with each stroke. Compatible with most cartridge grips on the market.