Features:Reference OE part number: 208479-00, ST5872H, H1BB-13D278-AC.Function: this headlight control unit provides the voltage needed to start the lamp and regulates the electrical current of the light once it is lit. A failed ballast will cause your bulb to burn.High performance: this headlight ballast is designed to meet or exceed standards of original factory headlight ballast. Exact fit for plug-and-play. Manufactured from quality material, high strength and durability, which has a long service life.Easy installation: this headlight ballast is engineered to stringent OE specifications, it is sure to exact installation and function the same or even better than the original part. Plug-and-play with no need to program or code the car.Compatibility: this h.