PPC Base Membrane 921 WT is a two-component, fast-curing, low-odor, NSF-approved liquid-applied aromatic polyurethane membrane, asphalt-extended for superior elasticity and durability. ANSI/NSF 61 approved up to 140°F, it is impervious to water and a wide range of aqueous chemicals, making it ideal for potable water containment, tank liners, pond liners, and corrosion protection on bridges and containment structures. With 450% extension to break, 98% recovery from full extension, proven weathering performance of 5,000 hours, and a service temperature range of -60°F to 200°F, it delivers a reliable, seamless waterproof barrier across the most demanding environments.