P-Line Halo Fluorocarbon Line is the future of fluorocarbon fishing line. Halo's Co-Fluoride design, which blends various pure fluorocarbon crystals, gives the angler the best combination of strength, sensitivity, castability, and invisibility under water. Halo has a higher specific gravity, giving the line a much faster sink rate. Because Halo is 100% pure fluorocarbon, it has a low refractive index making it nearly invisible underwater. The mist green tint has been optimized for use in lakes, rivers, streams, and inshore saltwater environments.