Hot-rolled steel has been used for more than a century for the construction of doors and windows. The hot-rolling process gives the profiles a very special and unique texture, which amplifies the natural and raw character of steel. Signs of rolling and slight surface imperfections, which architects and designers called “beauty marks”, constitute the distinctive character of this material and make it very popular for profiles of particular slimness and elegance. The corners of windows and doors made from hot rolled steel are always welded. Depending on the desired visual quality, welds can be either left natural or ground flat. Often welds are emphasized by brushing them to a silver metallic shine or blackened with special patinas. The FerroFinestra W20 and FerroFinestra W40 series re-introduce hot rolling in the original production method of the Thirties, updated with the application of modern technologies.