This Dragonhawk tattoo cartridges needles diameter: #12. Polished, long taper; reliable for all-purpose work. One piece needle and plunger overmold allows for maximum stability and control. Membrane mechanism prevents ink spitback. The membrane and tip of these needles allow artists to enjoy a more fluid tattooing procedure; Compatible with all rotaries/coiled machine, pen style tattoo machine. Comes in 20pcs Ethylene oxide (EO) gas sterilized and individually packaged; single use only Indentation at tip enhances ink flow and saturation.