The Rovex Fluorocarbon Leader is as close to invisible as is possible! It sinks rate is four times faster than that of normal Mono and has an excellent abrasion resistance. It is made from premium-grade 100% PVDF, which stands for polyvinylidene fluoride. PVDF is a material with properties that make it the most highly-regarded fluorocarbon for fishing leader for several reasons: Its optical density is lower than mono, making it less visible to fish. It has a harder surface, which increases its abrasion resistance. It doesn't take up water and it's also resistant to UV light. PVDF is denser than mono, so it will sink faster and will not float. All this jargon simply means that when you need the most invisible leader possible, with better abrasion resistance, and you don't mind it being a tiny bit stiffer, then Rovex Fluorocarbon Leader is your best choice.