A complete series of sinking lines designed for easy distance and complete fly control Easy casting, fast loading head for minimum false casts and quick distance Hang Marker shows where to fish The Hang Density Compensation for complete depth control Built on a supple core that wont tangle RIO Fathom lines are a series of sinking lines designed specifically for the lake angler. Each line has a short, quick-loading head for minimizing the number of false casts, and for quick, easy distance, and a color contrast between the head and the running line to easily show the lines loading point. In addition, each line is built with a Hang Marker that shows anglers when to stop stripping, and when to fish the hang, and features RIOs Density Compensation (except type 7) for complete fly control. DualTone- Marks the sweet spot of a fly line by providing an obvious color change in the line at the sweet spot. EasyID - RIOs printed line marking system that allows anglers to quickly and easily identify each line. Front Welded Loop- A neat, bulletproof loop welded at the front of the fly line for fast rigging. Back Welded Loop - A neat, bulletproof loop welded at the end of the fly line for fast rigging to backing. Density Compensation- Adds a denser material to the thin tip of a sinking line (or sink tip), which ensures the line sinks straight. Hang Marker - A visible, 1 section built into the fly line that show anglers when the end of the sinking line is getting close.