The crystal-clear plastics Plexiglas and polycarbonate, for example, are much stronger than glass, but also more sensitive to scratches. Plastics that are usually used in visual applications, where their appearance is important, are delivered from the factory with a protective film. Industrial plastics for which this does not apply, or to a lesser extent, and whose surface is still being processed in most cases, do not have a protective film. There may be light scratches on it as a result of shifting in the production process or during transport from the manufacturer. That is hardly ever a problem, but it is good to know and to take into account.