There are two sets of tattoo needles - those used for lining, and those used for shading. Some tattooists will use the different types of needles with machines specifically designed for them, eg, lining and shading machines, however many tattooists will use both lining and shading needles with the same tattoo machine.
tattoo machine, and the number of needles can vary. The needles are attached to the the tattoo machine's needle arm which is what makes the movement happen, and the needles are surrounded by a sanitary tube which can be taken off so that it can be sterilised in an autoclave. The sanitary tubes are designed especially for the combination of needles, so there's a seperate tube for each different number of needles in a needle bar assembly.
Liner needles come in combinations of 1,3,4,5 & 7 (there can be any number, but they're most often found in these combinations) needles per bar, are madeof stainless steel, and are usually arranged on the round bar in a circular pattern.
Shader needles most commonly come in groups of 4,6,7 & 9 needles, and are usually arranged in a straght line on a flat bar, much like the teeth of a comb.
Tattoo needles in professional studios are single-use to stop infection of any kind, and often come in blister packs.
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