PermaBase® BRAND Cement Board is a rigid substrate made of Portland cement, aggregate and glass mesh that provides an exceptionally hard, durable surface that is able to withstand prolonged exposure to moisture.PermaBase offers a competitive advantage over similar products on the market with its patented EdgeTech® technology. The tapered, double-wrapped edge design allows for closer nail or screw application to the edge.PermaBase is ideally suited as an underlayment or backing surface for tub and shower surrounds, countertops, flooring and a variety of other interior and exterior applications.