Rear tail Marabou plus a few strands of Flashabou (1-2 plumes)
Rear collar Palmered schlappen or webby hackle (1-2 feathers)
Body Ice dub or estaz chenille (as needed)
Front hackle/collar Schlappen and/or rubber legs, barred (few)
Wing/topping Flash and craft fur or marabou (small bunch)
How to tie it
On the trailing hook, tie in a full marabou tail about a shank-and-a-half long with a few strands of Flashabou each side, then palmer a schlappen collar forward to build a dense, mobile rear profile.
Wrap or dub a short body forward on the trailer, whip finish, and set it aside.
Lash a stout wire/braid loop (threaded with a couple of beads) to the front shank and mount the trailer hook on it so the two sections ride roughly a shank apart; secure the joint hard.
Tie a pair of dumbbell eyes on top of the front shank near the eye so the fly rides hook-point down.
Tie in a second marabou/craft-fur wing and flash on the front section, then dub a full body back to front around the eyes.
Palmer a schlappen collar and add a couple of barred rubber legs at the head, build a neat thread head around the eyes, whip finish and cement for a big, water-pushing profile.