Detailed Product Description With integrated material made of hemlocks of the virgin forest in North America and German Superior hardware fittings, they are produced under the German standard. They are not only harmonious with the decoration of rooms but also naturally beautiful, durable, corrosion resistant and non-deformable, so they can be regarded as the excellent products of their kind. The high-quality material and elaborate designs make Comfortone doors and windows energy-saving, green, corrosion resistant, sound insulating, waterproof, elegant and beautiful.