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MARISEAL® 250 is a premium, liquid-applied, highly permanent elastic, cold applied / cold curing, one component, polyurethane membrane used for long-lasting roof waterproofing. A solvent based, polyurethane roof waterproofing coating technique, MARISEAL® 250 is based on pure elastomeric hydrophobic polyurethane resins. This unique method delivers superb mechanical, chemical, thermal, UV, and natural element resistance properties. MARISEAL® 250 cures by reaction with ground and air moisture.