A compact, portable resistance heating device that takes a source of alternating current electricity and through a series of connections and circuitry splits the alternating current electricity into a plurality of circuits. The compact, portable resistance heating device is capable of heating a plurality of cartridge heaters at one time, individually or a combination thereof. The compact, portable resistance heating device is controlled by at least one controller that controls three (3) power output receptacles. The controller is capable of producing 0-100% output power to each respective cartridge heater. Each cartridge heater may be individually controlled by an on/off switch, and an indicator light may be provided and illuminate when each cartridge heater is energized. The cartridge heaters of the compact, portable resistance heating device do not require close tolerances with an axial bore of a stud or threaded bolt and are further capable of being bent to suit the particular operation.