The Hologram is a fly pattern we created to catch trout who are not aggressively feeding. This fly has a slim body to it so it can sink through the water columns and into the strike zone quickly. It has a dark profile for picky fish while at the same time having a ribbed body where it changes colors when the sun hits it just right. This allows the fly to get the fishes attention while not being too flashy to scare the fish away. This would be a great pattern to use on high pressured water such as the Boise and the Owyhee River. We generally like to fish this in sizes 14-18 as the bottom fly on our rigs. With that said, it has also treated us well fishing it in bigger sizes as the top fly. Overall, this is a great pattern and is one of our most used patterns on high pressured water. I would encourage you if you haven't already, pick some of these up and give it a shot on your next outing.