UNIQUE CREATIV TRULOCK serging thread is a 100% polyester 40 wt thread for overlock and serger sewing. The 1500 m (1640 yd) cone supports long, efficient runs for seams, rolled hems and edge finishing on apparel, accessories and home décor projects. The polyester construction supports durable stitching and easy everyday care. Use with a compatible serger or overlock machine and match needle, tension and stitch settings to the fabric.