Hi-Vis fibers are slightly more coarse fibers than spooled Antron with luminescence similar to seal fur. Its trilobal flat surfaces reflect much more light than a round fiber. Great material for spinner mayfly wings, upright dims, emerging nymphs or caddis downwings and spentwings. An equal or possibly superior material to spooled Antron for caddis pupa bubbles and trailing shucks on dry flies and emergers. These fibers also work well for sculptured streamers and wing material for steelhead and salmon flies.