Berkley Vanish Fluorocarbon Fishing Line - Easy-casting Berkley Vanish has become a popular mainline fluorocarbon in the U.S. and Canada. We have been continuously improving the Vanish formula since it was introduced 15 years ago, to ensure your satisfaction. The Easy Casting Fluorrocarbon; Remains clear under water - 100% fluorocarbon refracts light similar to water; Sinks under water - more sensitive and a more direct profile from rod tip to lure; Optimal Wet Strength - Non-absorbing fluorocarbon maintains strength and abrasion resistance under water; Flexible - Traditional fluorocarbons are stiff, Vanish is designed to be more flexible;