This fly developed after a tour last summer of Hareline Dubbing and a conversation with Marcos Vergara regarding the fish attracting properties of their UV materials. He referred me to a book titled, The New Scientific Angling - Trout and Ultraviolet Vision. The author does a decent job of presenting the limited scientific evidence regarding UV receptors in trout eyes and in the UV reflective body parts of hatching aquatic insects. There is scientific evidence that the UV spectrum penetrates the water to a greater degree than the rest of the light spectrum. I decided to do my own research and let the trout decide.