Quick-start voltage stabilization design, instantly light up the headlights with stable brightness and no flicker, improve driving safety Waterproof and shockproof high temperature resistant structure, adapt to complex road conditions and bad weather, longer service life 89393773 LED module for A5 for Q7 headlight control unit driver Function: Another key function of the ballast is to keep the headlights running continuously and ensure stable output. After the electrode arc is established, the ballast reduces the voltage and regulates the current Features: The automotive ballast assists the headlights in working more stably, ensuring normal start-up under both high and low voltage conditions, Manufacturer: JIIYP