Scientific Anglers Sonar Titan IntTriple Density Sinking Fly Line Get this: Scientific Anglers took one of their most popular tapers, the Titan, drenched it in various mixtures of tungsten powder, and created a triple density sinking fly line that will absolutely change the way you fish streamers forever. This is a fully tapered sinking line, so it casts like a floater, but provides a straight line sinking connection to your streamer. The days of chucking and ducking are finally over.