Metal-encased, tubular, hermetically sealed, metallized teflon capacitors which reduce the volume per microfarad of capacitance up to one fourth that of conventional teflon dielectric foil capacitors can be fabricated on a production basis. These capacitors are designed to operate over a temperature range of -65 C to 200 C and are capable of withstanding the severe environmental conditions. Available winding machines were modified for the winding of thin teflon film because of the films tendency to distort in both width and thickness when not held under constant or controlled tension. These modifications were all directed toward the exertion of constant tension on the winding material thereby alleviating major winding problems. The composite-type construction employing one aluminum metallized teflon electrode and one standard aluminum foil electrode was used in the construction of the capacitors. Lead attachments were made by spraying the ends of the capacitor with a high temperature aluminum solder. The capacitors fabricated using multiple layers of material were satisfactory upon completion of load life testing for a period of 1000 hrs with a 140% of rated voltage at a temperature of 200 C. However, the capacitors fabricated with single layer material failed the 1000-hr load life test because numerous momentary breakdowns weakened or destroyed the connections between the sprayed and connections and electrodes.