One of the most popular fly lines for many years now, the Scientific Anglers Mastery MPX line provides the ultimate in freshwater and light saltwater versatility. A redesign of the popular Scientific Anglers GPX fly line, this line is built as a do-it-all freshwater line great for lakes, streams, rivers, and more. Whats better? The lines taper and design cater to a variety of angling methods, including streamer fishing, dry fly fishing, and heavy nymphing. If youre looking for the most well-rounded, versatile line on the market, youve come to the right place.