Yep...that's what I was trying to think of. Never gave it much thought as I always thought that they were just trying to TM a tying style that could be done on any hook. There is another hook out there and I also apologize for not remembering the name of it. I have some at home in my flytying desk and many years ago entered a flytying competition with a fly tied with it but was a mayfly. I believe the hook was called an elephant hook or something Umbrella hook...see below post...which allowed the hook to be below the surface in a dropped style much like this: And just for clarification, the USD fly pics were from conversations that I had years ago when I lived in the UK with Roy Christie. I believe it was right at the time when he first came out with an article on USD tying. Its hell to get old, I can't remember all the sorted details. I do remember though that they are true-to-hatch but cannot speak to the hook-up ratio as I don't fish them. To each his own on tying style. I tend to think that the enjoyment comes in many ways; be it from tying in an unconvential style or from finding out that the style actually can catch fish. I tend to take more enjoyment from my tying than my catching but also understand that not everyone feels the same as I.