Hook Gamakatsu SC15 (saltwater-rated, light wire), 8 to 1/0
Thread White or to match the belly Lagartun X-strong 75 denier gel-spun
Materials
Body/weight Silver metal tape (Tungsten rib body ("half football"), medium on a size 2)
Belly Pearl anti static bag strip (Ice Dub, laid in as a hank then dubbed over)
Blend Silver metal tape (Ice Dub, blended forward from the pearl)
Head Black ostrich herl (Ice Dub, blended in at the front)
Back Natural case (Zonker strip, about 2", pierced and threaded over the hook point)
How to tie it
Lay a thread base on the bare shank.
Mount a tungsten rib body — the flat-sided "half football" — so the flat face sets the fly up to ride hook-point-up. Match the size to the hook; medium suits a size 2, large if you want it deeper.
Take a long hank of pearl Ice Dub, keep it straight rather than dubbing it, and tie it in just behind the tungsten body so it reaches back about one and a half shank lengths.
Bind the remaining hank down with open wraps forward, then back over itself.
Dub a liberal layer of pearl Ice Dub over that base, then run the gel-spun thread back through the dubbed body. This double layer is what stops the belly wearing off, because this face of the fly rides against the bottom.
Dub the second layer forward, starting with pearl to about the halfway point.
Blend into silver, then into black at the front, mixing the colours where they meet so the transition reads as a gradient rather than a band.
Cut about 2" of zonker strip, pierce the hide at its centre, pop the hook out of the vise and thread the strip over the point so it lies along the back.
Re-seat the hook in the vise, lock the hide down, and finish the head.