METACRYLICS W201 is a knit fabric designed to prevent moisture penetration with higher elongation and strength than standard fabrics. W201 is flexible in every direction and is ideal for use on any smooth or irregular roofing surface. W201 also offers a better perm-rate than other fabrics, giving the system an added layer of strong reinforcement that does not absorb as much coating as standard fabrics. This is often used with silicone coating systems.