These handy little gizmos are so versatile. They can be used as stitch stoppers at the end of your needles. Or, if you have interchangeable needles, put a stitch lock on the end of your cable when you remove your needle. Slide them on your circular needle cable when knitting magic loop to keep your knitting secure in your project bag. Or, if you are knitting a large project, use them on your cable to move your stitches closer together for easier knitting on those super-long rows! I've personally tested them on needles ranging from 2.75-6.5 mm (US 2-10.5) and they are definitely now a part of my knitting "tool kit"!