400 Series Contractor’s Choice is Top Quality Landscape/Filter Fabric. At 4 oz. this product shares the same characteristics as our 600 Series (6 oz.), but can be substituted on cost conscience landscape jobs or used in light to medium duty stabilization and filtration applications (great behind retaining walls). This American Made fabric is constructed of 100% Non Woven polypropylene for long life, and is easy to cut and install with any blade or razor.