The needle of system 3201 has a medium ball point for working knit fabrics, without damaging the stitches. It is used in industrial overlock, coverstitch and safety-stitch machines for elastic knit fabrics. Suitable machine classes are found, among others, at Brother (classes LK3, LX3), Singer (classes 68, 69, 115, 269) and Productos Sigma (classes B, LK 3).
Thinner needle sizes are used, among others, for fine, light jersey and tricot fabrics, and the thicker versions for heavy, dense knit fabrics and technical knits. As sewing thread, a matching thickness is usually recommended depending on the needle size chosen, e.g. from Amann Serafil or Rasant; for very stretchy seams, a texturised thread also works well. The ball point glides between the loops instead of piercing them, keeping the seam clean and undamaged.
