60 wt bobbin thread. Each spool of Aurifil Cotton Makò is mercerized - this enables fiber's contraction and increases the efficiency during the drying procedure. The result is a high sheen thread with a great washing resistance. The superior, long staple cotton boasts high tensile strength and a wonderful silky touch. The finest of the cotton Makó threads. Using this slightly thinner thread in the bobbin will result in a flatter seam. Imported from Italy. Large spool contains 1531 yards. 100% long staple Egyptian cotton.