Aurifil Cotton Thread — Black 2692 — Medium 28wtLooking for a matching Kona solid? Try Kona 1019 Black Aurifil thread is known among quilters as the best cotton thread you can find due to its versatility, strength, lustrous colour, and the fact that it produces virtually no lint. The 50wt thread is wound on an orange spool is the ideal weight for piecing because it results in flat, non bulky seams. It is a fine, strong thread that virtually disappears. The 40wt thread is wound on a green spool.