Features The Foil Heater is a self-contained one-piece assembly. A resistant element is laminated between two layers of aluminum foil. The heater is ideally suited for area and surface heating applications. Sheath temperatures to 300°F. Widths range from 1 1/4\" minimum -36\". Lengths range from 4\"-60\". Heaters are available with a thermostat. Many configurations with or without holes and cutouts are available.