Hailing from Michigan, Mr Lynch's now-famous streamer is a trophy fish catcher. The Double-D (D-Squared, D&D, D-Nasty, Heavy DEEE) is designed to move, shimmer, and shake. It has more shakes than Shake Shack.
The movement comes from three places. First, the materials themsleves shimmer and pulse. Second, the articualtion allows the fly to achieve a swimming motion. Third, the shape of the spun deer hair head creates random movements that mimic a swimming -- and possibly wounded -- baitfish.
The size 2 has two hooks and measures ~5". We dare you to try it.