Yo-Zuri Topknot Fluorocarbon Leader material is Natural Clear and virtually invisible, Abrasion Resistant, Shock Resistant and Super Durable which maintains its clarity even after extended use. This allows the angler to get even more strikes on the same line. The most pressing feature, however, is the diameter to strength ratio. The TopKnot series offers the strongest possible breaking strength with an even smaller diameter than before. This is a must have product for any angler!