Window film is a thin laminate film that can be installed to the interior or exterior of glass surfaces in automobiles and boats and also to the interior or exterior of glass in homes and buildings. It is usually made from polyethylene terephthalate (PET), a thermoplastic polymer resin of the polyester family, due to its clarity, tensile strength, dimensional stability, and ability to accept a variety of surface-applied or embedded treatments.
Window films are generically categorised by their construction components (dyed, pigmented, metallized, ceramic or nano), by their intended use (automotive, marine or architectural), by substrate type (glass or polycarbonate), and/or by their technical performance (privacy, solar control, safety and security).
Window film is normally installed by professional service companies but there are also DIY kits widely available.
The International Window Film Association, founded in 1991, provides unbranded information about window films.