Torchflex TP-180-Cap Heat Welded Cap Sheet is constructed using a tough non-woven reinforced polyester mat strengthened with select glass fiber strands. The product is coated top and bottom with select SBS polymers and premium quality asphalt. Ceramic coated mineral granules are embedded into the surface to provide protection against ultraviolet radiation. A light micro-perforated film is bonded to the underside and conveniently disappears upon heat welding. Torchflex TP-180-Cap is an excellent choice for the top ply in either a BUR system or a two-ply modified system.