This handy double-ended crochet hook is attached to a keychain, so you can keep it with your keys or knitting bag at all times. One side of the crochet hook is 2.0 mm and the other end is 3.5 mm, which is handy if you are working at large or small gauges. Use the crochet hook to pick up the dropped stitch, and carry it up the ladders until you can return it to your knitting needles.