Zinsser WaterTite Polyurethane Sealant is a high performance, low modulus, single component, moisture-cured modified polyurethane joint sealant. It is designed to fill deep cracks and holes, seal dynamically moving joints such as expansion and control joints, precise concrete panel joints, tilt-up panel joints, curtain wall joints and perimeter caulking to windows, doors and panels. It is suitable for use on concrete block, cast-in-place concrete, stucco, tilt-up, exposed aggregate and slump block.