This EPDM rubber pre cut and boxed pond liner can be used for building all types of ponds, water gardens, basins for fountains, bog gardens, lining cracked hard shell ponds and other applications. The pond liners 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. pond liners retains its high flexibility even in cold weather. It can easily be shaped to fit the unique contours of any pond. Pond liners shows outstanding resistance to the harmful effects of ultraviolet radiation (U.V.), ozone and other environmental conditions. pond liners exhibits a high tensile strength and an outstanding resistance to puncture and, once installed, requires little or no maintenance. pond liners is specially formulated to be safe for exposure to fish and plant life in decorative ponds while resisting microbial and algae attack. It is safe for fish and aquatic plants. Pond liners black color gives a natural look that blends with the algae that frequently grows after several months. The black color also lends greater U.V. protection while giving the illusion of greater depth. Measures 20-feet length by 20-feet width by 0.045-inch thick.