The ceramic-sheathed immersion heater is designed for use in molten metal baths, abrasive and corrosive service, at high-pressure, vacuum and other extreme temperature applications. It can supply temperatures up to 2100 F (1150 C) for direct immersion in processes. It is suitable for direct immersion in molten aluminum and is impervious to aluminum dissociation. It also is designed for use in fluidized bed and catalytic reactors for processing highly corrosive and acidic fluids, gases and vapors. The units operate up to 480 V in single- or three-phase configurations and have a watt density of 60 W/in.2 maximum.