The MFM SubSeal40 Waterproof House Wrap 40 millimeter is a waterproof membrane composed of a polymer film with a layer of specially formulated, rubberized, asphalt adhesive suitable for use on siding and exterior plaster. This waterproof house wrap combines strength and flexibility to create a SubSeal foundation water barrier for walls, exterior walls, through-wall flashings, around doors and windows, underneath stucco, plaster and masonry, planters, pot shelves, and as a flashing material.