Marabou (tail) Black marabou (1 clump, hook-length)
Flashabou (body) Brown holographic flashabou (2 strands)
Copper wire, medium (rib) Copper wire (1 length, 4-5 turns)
CLX dubbing brush (first collar) Nightmare Red (2-3 wraps)
CLX dubbing brush (second collar) Black Stone (2-3 wraps)
How to tie it
Seat the 1/8" chartreuse tungsten bead with its small diameter forward and build a small thread dam behind it to hold it in position.
Cut a clump of black marabou to about one hook-length and tie it in at the bend as the tail.
Tie in the medium copper wire at the bend and leave it hanging for the rib.
Tie in two strands of brown flashabou behind the bead, bind them back to the tail, return the thread to the bead, then wind the flashabou forward to form the body, covering all the thread.
Counter-wrap the copper wire forward in 4-5 open turns, tie it off at the bead, and helicopter the wire to break it away.
Tie in the Nightmare Red CLX brush behind the bead, pull its fibers back, and take 2-3 wraps for the first collar, sweeping the material rearward as you wrap; tie off.
Tie in the Black Stone CLX brush and take 2-3 wraps over the red so it part-veils the first collar; tie off behind the bead.
Whip finish a couple of times behind the bead (head cement optional).
Pick out both collars with a dubbing pick, sweep everything back, and lightly break the longest fibers with scissors so the fly tapers into a thin leech body.