Sunline Siglon FC Flurocarbon | 50M100% fluorocarbon & 1. 78 high specific gravity. Fluorocarbon line with excellent balance of tensile strength, knot strength and stretch. Unique TRP processing for better slickness and abrasion resistance and more perfect knoting. Low water absorption for negligible strength loss underwater. Just the right amount of stretch like nylon, but with good sensitivity due to low initial elasticity.