Aunt Lydias Extra Fine Crochet Thread. High luster mercerized cotton thread Aunt Lydia's Classic Crochet Thread is perfect for delicate crochet projects both large and small. Available in traditional colors Aunt Lydia's Classic Crochet is ideal for heirloom-quality home decorating and fashion projects Features: size 30 100% mercerized cotton 500 yds./457m. Recommended crochet hook: 12 (.75mm). Care: machine wash gentle ( 104F/40C) roll in towel & block do not bleach do not dry clean do not iron. Imported.