The Knook makes it easy to create a knitted look without knitting. It is a specialized crochet hook with an eye at the end for a cord to go through. The cord keeps the stitches from unravellling as you knook. A strong smooth finished cord is required for knooking (i.e. - rattail). Set includes 2 aluminum The Knooks sized 2mm / US-1 and 3mm / US N/A.