YLI Nylon Bobbin Thread is very strong with little stretch. Its excellent in the sewing machine or serger, on nylon tricot, or light weight woven synthetic. It is an excellent bobbin thread for machine embroidery, machine beadwork and lingerie construction. YLI Nylon Bobbin Thread comes in Black or White, 100% nylon, and is 1200 yards per spool. These threads are very economical, lightweight, and allow you to wind a great deal onto your bobbins. This means you won't have to re-wind your bobbins as often. The fine nature of this bobbin thread makes it a great choice for delicates and lingerie.