Most Schmetz Needles include two color-coded bands just below the shank. The top color indicates the type of needle, and the lower color indicates the size. The Schmetz Serger Needles do not have a color code. Schmetz BLx1 Serger Needles is a pack of five needles in a plastic case that slides shut for safe storage. The needle system, needle type, and needle size are printed on the front of the case.