KLASSE stretch needles are designed for two-way stretch knits, including fabrics with Lycra or Spandex, and for sewing elastic. This pack includes stretch needles in size 75/11 for domestic sewing machines used on swimwear knits, lingerie fabrics, and other high-recovery synthetics. The specially designed scarf helps reduce skipped stitches, and a test seam will help you fine-tune stitch length, tension, and presser-foot pressure.