Sulky 40 Wt. Rayon machine embroidery thread has the same luster and soft, warm, natural look as silk with silk's smoothness, but it is stronger than either silk or cotton thread of the same weight. It won't fray, fuzz or shrink and it has less stretch than Polyester so it is the thread that most digitizers use as the standard for their embroidery designs. Sulky 40 wt. Rayon Decorative Thread is thicker than a 50 wt. regular sewing thread, for faster, fuller coverage. Ideal for computer machine embroideries, quilting by hand or machine, blanket stitch, appliqueing, top stitching, flat lock serging and rolled edges. Machine washable and dry cleanable. Recommended Needle Size: 12/80 or 14/90 Embroidery Needle.