In place of using only spray paints and markers to deface glass and other smooth surfaces, vandals are also using glass-etching solutions. Whether applied to windows, public transportation, transit stops or even bathroom mirrors, 3M Anti-Graffiti Window Film provides a strong initial line of defense against paint, gouging, scratching, and even acid etching. If the damage is done, simply replace the film for the fraction of the cost of replacing the entire window.