Seaguar Fluorocarbon Spools; the inventor and world leader in 100% fluorocarbon leader material, Seaguar Fluorocarbon is preferred by professional fishermen the world over for its ultra-low visibility, tensile and knot strength, and superior abrasion resistance. Seaguar is the top choice for all trolling, live lining, chumming, and chunking situations. Seaguar is the only fluorocarbon leader manufacturer that blends its own resins; giving it greater knot strength, higher tensile strength, heavier molecular weight, and superior abrasion resistance. 34% better knot strength than leading competitor fluorocarbons. Fluorocarbon leaders' advanced strength allows use of smaller pound test vs. other fluorocarbons for more effective presentation. Incredible impact strength, knot strength and abrasion resistance. Ideal for larger species in fresh or salt water. As with all 100% Fluorocarbon products, FC Leader is much less visible underwater than monofilament line and virtually invisible to fish. FC is also UV resistant, chemical resistant, non-absorbant, high-density and impervious to cold conditions. Made from 100% Seaguar resins and produced using their proprietary extrusion process.What are the differences between Seaguar fluorocarbon Leaders and Seaguar fluorocarbon Lines? Strength - While both are strong and will withstand the lb test listed, leader and tippet are stronger over shorter lengths and are not designed to be a long, main line product. The main lines are designed to take the impact load over a much longer distance, transferred throughout the line.Double Structure Technology - Seaguar's Big Game Fluorocarbon and Fluorocarbon Premiere are all Double Structure, (2 to 80 lb), a Seaguar exclusive process that injects two different molten resins through a special die. The resins are extruded as one solid piece. The harder, inside resin contributes to the Tensile Strength, while the softer, outside resin creates greater Knot Strength.