This yarn is an excellent substitute for dubbing on flies. It makes a great simple Walt's Worm, Sawyer's Killer Bug, or hare's ear type body as well as a body for Czech nymphs/caddis larva. It is small enough I've used it on a size 20 but can be wrapped loose and built up to use on larger flies. (Devin) Here's what Semperfli says about it...