Alliance Gator NGF35NW-12400 12' x 400' Gator GF3.5 Non-woven Fabric - Gator GF3.5 is a needle punched non-woven geotextile made of polypropylene fibers. It is ideal for drainage, filtration and will allow water flow of 165 gallons per minute per square foot in paver or retaining wall applications. Its filament fibers are used for soil separation and drainage. They combine high durability along with excellent physical and hydraulic properties. It is non-biodegradable.