Scientific Anglers Sonar Triple Density Intermediate/Sink-2/Sink-3Head sinks 2. 5 3. 5ips. Pale Green running line, Blue center and Dk Green head. WF6S thru WF10S. SONAR TRIPLE DENSITY SINKING FLY LINES: These lines will absolutely change the way you fish streamers forever. These are fully tapered sinking lines, so they casts like a floater, but provides a straight line sinking connection to your streamer. They load quickly and deliver the biggest flies to the furthest targets. Shooting texture reduces friction,