The EPDM Pond Liners are durable 45 mil EPDM rubber that is weather and UV resistant. These liners are the preferred choice for professional pond installations. They are extremely flexible and very puncture resistant. These EPDM liners have been tested and proven to be safe with fish and plants. Hightly flexible EPDM liners remain flexible in extreme temperatures. Weather resistant EPDM liners are UV resistant . EPDM liners are so durable they are under limited warranty for twenty years! Available in various sizes.