JINKAI Fluorocarbon is a very low visibility line. It was especially developed to give fishermen a greater advantage in catching leader-shy fish. With a specific gravity of 1.78, fluorocarbon sinks faster in water than do conventional leaders. It has excellent transparency, becoming almost totally invisible in water. With a Refractive Index [RI] of 1.42, fluorocarbon comes closer to the 1.33 RI of water than any other leader material. Fluorocarbon line does not absorb water as nylon line does; its strength is the same, wet or dry. And JINKAI Fluorocarbon line has excellent impact strength, knot strength, and abrasion resistance, holding up well, fish after fish.