Sea Striker Billfisher Leader Coils are formulated from a special polymer that is extremely strong for its diameter, has excellent resiliency and has superior abrasion resistance. Â All the properties you want in a Big Game leader material. Â Hard outer shell and soft inner core that remains flexible. Bill Fisher monofilament fishing leader can be used for rigging lures or live baiting. Â Makes an excellent leader for Marlin, Tuna and Grouper. Â Available in 80 to 400 pound test. Â Clear, 100 yard coil