Fluorocarbon construction refers to fishing lines and leader materials that are either entirely made of fluorocarbon polymer or have a fluorocarbon coating on their surface. A key property of this material is its refractive index of light, which is almost identical to that of water. As a result, such a line is very difficult for fish to see under the water surface. Compared to classic nylon lines, fluorocarbon is also denser, and therefore sinks faster. It is also characterized by higher abrasion resistance and lower stretch, which allows for better sensitivity in bite detection and more direct contact with the bait.