A tattoo needle is actually (usually) a group of several small needles called sharps attached to a needle bar. Needles can be made in groups of 3, 5, 7 or more, depending on what the artist is comfortable with and what the design calls for. Occasionally, a single needle can be used for fine lining, but this is not very common. The sharps are soldered to a needle bar, and the bar is placed in the tattoo machine through a tube. Needle groups also come in different shapes such as round (for lining) and flat (for shading).