Mettler Cotton 1243 Sm Black Iris. Both solids and multi's are perfect for all your quilting, sewing and long arm cotton needs. The mercerization of all Mettler cottons creates that beautiful silk-like sheen, high breaking resistance, color fastness and optimal elongation. Use Mettler's SILK-FINISH COTTON 50 with confidence to create your heirloom quilts, custom garments and creative projects. Tex 32. Manufacturer recommends needle size 80-90. Old color number 105-0688 or 105-688.