The Scientific Anglers Sonar Titan Int / Sink 3 / Sink 5 Fly Line is a triple density sinking fly line with an aggressive taper for large flies. The running line is an intermediate sink, then a type 3 in the handling section and a type 5 sink in the tip. The sinking profile helps keep a straight connection to your streamer for secure hook ups. This is an absolute favorite for pike/musky fly lines and other large predators. Scientific Anglers Sonar Titan Int / Sink 3 / Sink 5 Fly Line Features: Loads quickly and delivers the biggest flies to the furthest targets Triple-density construction provides straight-line connection to fly Excellent turnover due to short, powerful head and short front taper Shooting Texture reduces friction, provides longer casts, easier pick-up, and increased durability For temperate climates Braided multifilament core