This small pattern packs a big punch. With the bright orange head and the natural body it will get eaten. I have fished these through hatches of both midges and Blue Winged Olives and had a lot of success!
My only warning with this pattern, and any that use UV resin to seal of the body is, do not clamp down too hard on the body of the fly with your forceps. If you exert too much force you may break the resin. If this happens, you can still fish the pattern just the same, but it will not be quite as durable!