DESC: Firestone PondGard EPDM rubber is the industry standard for 45 mil decorative pond liner. The PondGard membrane is based on ethylene propylene diene monomer (EPDM) synthetic rubber, a highly flexible yet stable waterproofing membrane with a proven performance history in exposed applications. PondGard retains its high flexibility, even in cold weather. It can easily be shaped to fit the unique contours of any pond. PondGard shows outstanding resistance to the harmful effects of ultraviolet radiation (UV), ozone and other environmental conditions. PondGard exhibits a high tensile strength and an outstanding resistance to puncture, and once installed, requires little or no maintenance. PondGard is specially formulated to be safe for exposure to fish and plant life in decorative ponds while resisting microbial and algae attack. It passed both the Environmental Protection Agency (EPA) and the American Society for Testing and Material (ASTM) International test requirements in regard for the safety of fi...