a)The base of colorful stone-coated metal roofing tiles is galvalume, as well as vermiculites processed by high technique on its surface. The multi-layer design is environment friendly as well as being in modern style. b)Compare to the galvanized sheet, galvalume is more durable, heat-resisting, heatproof and anti-corrosion. It is generally believed that steel sheet can guarantee 30 years without being rusted or eroded in various conditions. c)The colorful vermiculite has been processed at high temperature, thus to be brightly-colored, and never faded.