Seaguar Fluoro Premier 50 50LB is virtually invisible. It has smaller diameters with incredible knot and tensile strength. This is a perfect shock leader that is extremely soft with a low memory. Seaguar took flourocarbon to the next level with this line. 100 Percent flourocarbon line Incredible knot and tensile strength 42 Percent better knot strength Nearly invisible in water Exclusive Seaguar resins