Matching a line to a modern fly rod can be quite the challenge. High quality rods require a slightly heaver line to properly load and transfer that potential energy into a cast. The Fly fisherman can trust that The Mastery Series Textured GPX Fly line will get the job done. The line is 1/2 size overweight of a standard fly line in each size making the action of loading and unloading that fast action rod a simple task. Designed for cold to moderate climates. The AST coating not only helps in shooting long casts but repels dirt and other sediments that may cling to fly lines causing them to sink.