HEAVIER SIZE "F-C PREMIUM FLUOROCARBON" TIPPET MATERIAL - I've trusted it on "once in a lifetime trips" throughout the world, and it has always performed flawlessly (Bob). It knots beautifully to other fluorocarbon or to nylon, and I have never once had a knot slip. F-C FLUOROCARBON absorbs light rather than reflecting it, making in virtually invisible in the water. Great knot strength. 4x more abrasion resistance then nylon. PLUS its density allows it to sink 4x faster than nylon. 30-YARD spools in Sizes: 15-lb, 20-lb, 25-lb, 30-lb