I asked my buddy who's a musky fanatic, and here's what he replied:
Hope this helps.It's called Surflon, its a nylon coated wire which is used for fly fishing
and is good leader material, I use it for pike leaders on my tip ups in the
winter, and if I do any fly fishing for skees or pike this is what I would
use for a tippet... A company called American Fishing Products makes it,
mostly used in saltwater flyfishing applications as a shock tippet. If you
want something thats easy to work with get the 25# or 36#, you can basically
tie a clinch knot or surgeons knot and heat it up and you have a leader.