Aurifil’s 100% Cotton 12wt thread is wound on a red spool. It is the heaviest weight thread that Aurifil offers and is perfect for hand applique, hand embroidery, hand quilting, cross stitch, embellishment, handmade lace, machine applique, blanket stitch, machine embroidery (especially for designs that use a longer stitch length), machine art quilting, Sashiko, redwork, lower looper serging, and longarm quilting.