Rainys Purple Pea Wee tied on a #12 hook
This nymph is commonly used on Euro nymphing setups, but is equally home finding trout under a dry fly or strike indicator. It's not exceptionally heavy, so don't expect to use this as an anchor fly.
Purple is a color that sometimes gets hammered by the trout. We're not sure why, or exactly what its imitating but certain days they are out of their minds for it. This fly has an extremely high quality hook, is well tied, and can often be the hottest nymph in the river.