(Price for 12 Flies) It is a simple but very effective. The Griffith’s Gnat is one of those tiny dry flies that experienced anglers never forget to carry in their boxes. … Wrap the peacock herl to shape the body of the fly . Wrap the rooster feather palmered up until it reaches the hook eye. and that’s about it. Very effective in many types of fishing situations for rainbow trout, brook trout and brown trout!