These Lines Feature Advanced Tapers Designed Specifically for Our Fly Rods with the Line Weights Adjusted to help Load our Rods more Easily than Traditional Lines. Each one has a Specific Core Designed for Freshwater or Saltwater that will Perform even in the Most Extreme Tropical or Cold Conditions. Finally, for Added Longevity, we added a Proprietary Built-In Line Lubricant to all our Lines.