Our Gabions and mattresses fully comply with ASTM Standard A974 in regard to the material used and the methods of manufacture. ASTM A974 establishes minimum requirements for all materials used in welded wire gabions as well as the manufacture and pre-assembly of the baskets and mattresses. The fabric used in the baskets is a 3" x 3" grid with wire that is either galvanized (11 Gage) or PVC coated (12 Gage). PVC coated is used in applications where greater durability is required or a different aesthetic appearance is desired