An even sleeker version of this fly that is one of my favorite trout flies for late evening in either stream or lake is the Royce Dam Rabbit Leech.
Hook: Loop Up Eye Salmon in #6- #10
Weight: Black nymph bead or cone pushed up over the hook return, use a quality hood that has the return loop finely tapered to do this. You can also use lead barbells, if so wrap the body over them or lead wire under the front 1/3rd of the body. The bead is faster and easier.
Tail: Red or Chartreuse Marabou, short, can use 2 strands of Krystal Flash or Flashabou in pearl if desired. I usually don't add the flash material.
Body: Black rug yarn or very fussy yarn
Rib: Oval Silver
Wing: Black bunny strip tied Matuka Style (held down against the body with the ribbing.
Hackle: Long, Soft and Black. I like to use dyed black pheasant rump.
Purple body with the black wing and hackle and a claret or burgendy body with the black wing and hackle are also very effective; however, black on black with red marabou tail is my favorite.
This fly swims beautifully (very similar to a real leech) with a slight jigging motion as you strip the fly back in short 4-6" strips with rather long pauses in between. The weight at the head of the fly with the black bead really helps to give it the proper motion. Fish it on a longish leader and have fun. This is also an excellent fly for bass and crappie.
Tight lines and good feather bending.