Material: Xenon H-ID headlight ballast control unit modules have passed extensive quality and reliable performance tests and are made of special materials to ensure stable performance and long service time. Function: H-ID ballasts control or adjust the intensity of H-ID lamps. The ballast provides the voltage required to turn on the lamp and regulates the lamp current when the lamp is on. Without the ballast, the bulb will consume too much power and burn out quickly, sometimes for several minutes. Installation: These ballast units are ready to install without any recoding/programming and can be installed on both the left and right sides. Quality: Made of materials that meet strict OEM requirements, this product offers stable performance and is an ideal replacement option. Note: To ensure you receive the correct item, please confirm that your OEM number matches the one in the description.