<p>It is possible to provide a low-cost neutralizer exhibiting high maintainability in which distortion and damage are prevented even if an electrode is expanded thermally. The neutralizer comprises a filament, a pair of electrodes for feeding a current to the filament, and a base for supporting the pair of electrodes under insulated state. The neutralizer is further provided with a means for holding the pair of electrodes and the base under such a state that the relative position between them can be varied in at least one direction.</p>
