Metrosene can be used on all fabrics and seams. The thread is easy-iron, shrink proof, and offers great color fastness. Metrosenes high tensile strength, optimal elasticity, and ideal smoothness makes it the sewists choice. Mettler recently changed the numbering system on these threads. 1145 is the original style number with the original thread color numbers. New thread color numbers can be found under style number 9145.