Firestone APP 160 is a smooth surfaced APP modified bitumen membrane. It consists of select asphalt, modified with atactic polypropylene, and reinforced with a non-woven 190 g/m² (3.9 lb/100ft²) polyester mat, enhanced with continuous glass fiber strands in the machine direction. APP 160 is ideal for both new construction and re-roofing applications as a base ply, cap sheet, or as a flashing sheet in single or multi-ply applications. Low slope roofs of any size, even those with numerous penetrations, may accommodate a Firestone APP 160 membrane application.