63128386960 D2S D2R Xenon Ballast HID Headlight Igniter Control Module for VW 3B0941641 6N0941641. Function: They control the current flowing through the bulb, thus keeping it lit and providing auxiliary illumination. Our headlight ballasts are made of durable ABS materials. This design prioritizes heat dissipation and shock absorption, ensuring it can withstand the demands of daily driving. Installation: This ballast retrofit kit is easy to install and perfectly compatible with your vehicle. No complicated operations or modifications are required; it is simple to use, saving time and effort. Customer Service: Please ensure the part number of your car ballast matches the part number you are replacing. If you are unsure, please feel free to leave us a message., Manufacturer: HNHLSM