Replace Part Numbe: 539-0117, 5390117, 539-0117-REV-02, 539-0117-REV-01, 539-0117-02. 539-0117 Nitrogen Oxide Sensor NOx Sensor For CAT Caterpillar. for CAT Caterpillar, application for off-highway vehicles as well as industrial, marine, and gas engines.
