Foam is a high-floating material that can be used for all kinds of fly tying applications. Use foil foam to make a killer beetle patter, or use furry foam to make the claws on your Clouser crayfish. Foam is ultra buoyant and will stay afloat longer then most natural fibers. You can get foam in sheets and cut to size or buy pre-molded bodies to make your tying easier. Either way using foam will give an advantage for tying high floating flies.