Scratches on lubricating film. Coloured scanning electron micrograph (SEM) of scratches on the surface of a lubricating film of molybdenum disulphide from a dry film anti-scuffing aerosol spray. The spray contains the lubricant, a volatile organic solvent and a small amount of bonding resin. The solvent quickly evaporates, leaving a layer of randomly-dried rings of molybdenum disulphide. These raised rings are gradually scratched and abraded with use, slowly smearing out to produce a thin film. Dry film lubricants have advantages over oils including not attracting dust and they can be used to higher temperatures. Magnification: x480 at 5x7cm size.