This is sort of a new fly for me. I just started using it a few weeks ago. It was recomended to me by a friend of mine. I fish it in sizes 18 and 20. I think fish are taking it for mides and small mayflies. But it is very effective in these sizes. They now have a spot in my fly box. As you can tell from my fly selection, I don't fish a guantlet of flies. I fish what works. Give them a try. These flies are tied to order.