Brilliantly reflective Sulky Holoshimmer™ Metallic Thread is a thin, flat, ribbon-like, (holographic) foil that is laminated with polyester, which makes it amazingly reflective so you can add the ultimate sparkle to all of your decorative projects. Works perfectly on sewing, serging, knitting machines, and for handwork. Recommended Needle Size: 14/90, 14/90 Metallic or 14/90 Topstitch as well as a vertical spool pin.