Some fish are afraid of their own shadow. Others have seen every fly known to man. So when you're up against the absolute pickiest of eaters, it's time to get technical.
The precision line that casts well on any action rod. Long front taper for beautiful turn over. Longer head for control at distance. Smaller tip diameter for presenting smaller flies. Haul zone extends usable head length. Ultra-thin running line shoots like hell, takes up less spool space.