PPL is pre-painted galvanized iron, also known as pre-coated steel, coil-coated steel, color-coated steel, etc., usually with hot-dip galvanized steel substrate. The term is an extension of GI, which is the traditional abbreviation for Galvanized Iron.Galvanizing protects the base steel by providing cathodic and barrier protection. The paint coating acts as a barrier protection to the hot-dip galvanized coating, significantly reducing the corrosion rate of zinc.