Our tattoo machine use aluminum space Aircraft Aluminum as structure.It is anodized to increase its durability.The body is compact,only 120 grams.It can be secant, Liner or Shader and of good stability.It can work long hours.the needle length is of 3.5 4.5 mm, and stroke length is of 3.5 to 4.5mm.Optimum voltage is  of 6-7 volts appropriate. This tattoo machine gain masters' widespread praise!