Traditional incandescent lighting illuminates around the perimeter of the dial. Gauge kit includes wiring harness bulb and socket assembly red and green bulb covers mounting hardware and detailed instructions for installation. Included wiring harness connects to original equipment High Pressure Oil Pump sensor wiring.. For use with 1994-2003 7.3L &. 2003-2007 6.0L Ford Powerstroke Engines ONLY. Autometers Race Proven Digital Stepper Motor Electric Instruments Provide Unmatched Accuracy While Keeping Hazardous Fluids Outside Of The Vehicle. The accuracy of digital stepper motor gauges is further increased by utilizing a self calibration sequence during power up. 12 and 16 volt compatible compatible with nearly every street car or race car electrical system