Trout feed on all stages of Caddis, but emerging caddis seem to be a little extra special. If you could snap a photo of an adult caddis just as it is emerging from its former larva body you'd have RIO's Body Double. This pattern sits with its back side below the water surface on a curved shank hook which best replicates the pupating caddis. The front half of the hook sits above the water line replicating the freshly emerged adult. The bleached elk wing makes it easier for the angler to see it, especially in the flat canyon light of evening. It comes in the three most effective colors and sizes, Tan (14-16), Olive (14-16) and Black (16-18). If you find your favorite Caddis pattern not getting the job done, it's time to send in the Body Double.