... certificate.(Polyester Sewing Thread) Polyester Sewing thread Features:a) (40s/3): used for tailoring, trousers, jacket, medium, heavy fabricb) ... (20s/2), (20s/3): used for jeans, upholstery PVC bags, canvas, footwearc) (40s/ ... , pants1) 20/2, 2000yards/3000yards/2000 meters/3000meters2) 20/3, 1600yards/2000yards3) 40/2, 3000y/4000y/5000yards/5000 meters4) ...