Scientific Anglers Amplitude Smooth Infinity Salt Fly LineScientific Anglers Amplitude Smooth Infinity Salt Fly Line, The Amplitude Smooth series of lines are, simply put, the highest performance smooth fly lines in the world. With up to five times less drag and eight times the durability of traditional lines, this will change the way you look at fly line performance. The Infinity Salt is technical, versatile, accurate and simply the most advanced saltwater line available. Featuring the revolutionary AST