That's essentially what it is. A soldering iron with a sharp blade (all different kinds of shapes) that gets really hot and when handled by a pro, cuts tire tread like butter. At a dirt track event the pits always have the sweet(?) smell of burning rubber! Pro rallyists use these to keep nice sharp edges and get the most use from expensive tires as well. We called it "dressing" the tires.WD40,
It looks like a giant soldering iron!