Japan's Matsuo Electric Polystyrene film (polyethylene terephthalate film) attached to metal foil electrodes. Radial leaded electrically welded windings of tinned wire and the entire 503 capacitor packaged in self-extinguishing material compliant with UL 94V-0 requirements. It is designed for high-speed applications requiring high frequencies and high du/dt with typical low electronic losses, audio-visual or video and telecom applications. Metal foil type (plastic) film capacitors have extremely low losses and low dielectric absorption of all-film dielectric materials. Has a very high dielectric strength and high insulation resistance, with a negative temperature coefficient. This metallized film capacitor has self-healing properties, in fact if a conductive particle or a surge voltage breaks down the dielectric, arcing occurs at the point of failure, melting the surrounding metal and insulating the breakdown zone. Dielectric breakdown in metallized plastic films causes reduced insulation resistance due to higher carbon deposition in the breakdown channel compared to paper film dielectrics.