Coated-sheet encompasses a range of cold-rolled products with thicknesses between 0.5 and 3 mm which are surface treated in order to combat corrosion.  Galvanising, either by the hot-dip or electrolytic process, is the most common method for protective coating but products with more sophisticated treatments having better corrosion resistance such as aluzinc, where the zinc coating is combined with aluminium, are also available.