100% fluorocarbon monothread, made by the Japanese company Sasame, that defined it super strong and excellent for durability. is a fast sinker that does not absorb water, unlike ordinary nylon. Remains unaltered by both UV rays and salt. Invisible in the water with a degree of refraction less than 60% compared to any other traditional nylon monothread. It is distinguished from the classic fluoro carbon for higher softness, hence the name soft, allowing a more natural bait presentation. Available in spools of mt. 250.