Goodfellow's PET Metallised Film with 20 nm Aluminium Sizes is a plastic film made of polyethylene terephthalate (PET) that has been coated with a 20 nanometer thick layer of aluminum metal. This metallized PET film combines the flexibility and chemical resistance of PET plastic with the reflective properties of aluminum. With high specular reflectance across the visible spectrum, these films find use as a reflective surface in packaging and optical filters. Goodfellow offers this metallized PET film in a range of thicknesses from 12 to 50 microns.