Armourplast Granular APP Modified Bitumen Membrane is constructed of a tough non-woven reinforced polyester mat strengthened with select glass fiber strands. The mat is coated with APP modified bitumen to a thickness of approximately 4.0 mm (158 mils). The surface of the product is covered with mineral granules to provide added protection against ultraviolet rays. A protective, micro-perforated film, which disappears during heat welding, is bonded to the underside of the membrane. Armourplast Granular APP membranes can be used as the top ply in a flashing installation or as the protective cap for a conventional BUR roofing system.