1. Premium quality Made of premium aluminum for better heat dissipation and vibration resistance performance. Also has 6 protections against overpressure, low pressure, overheating, no load, short circuit, reverse connection for more and durability. Built in high pressure bag can speed up current conduction speed save power consumption for fast startup. 2. Replacement A ballastIt is a crucial part of a fluorescent or HID lighting system. It provides enough voltage and current throughout operation and regulates the electrical current of the light once it is lit. It can act as DC to AC converter so that you can use the normal DC power source in the car to light the bulbs efficiently. The most common cause of HID Ballas failure is long term use, which can result in flickering, dipped beam not working or light failed. 3. Powerful function shockproof performance the internal circuit board is treated with adhesive glue irrigation, protecting internal electronic components from oxidation aging. It can help your lamp start up quickly. When the lamp is turned on, the ballast provides a surge of higher voltage, then establishes an arc between two electrodes on the lamp and reduces the voltage and the electric current. This ensures the light produced is even and steady, without flickering or fading. 4. Reference OE1 307 329 293, 307 329 115, 1307329115, 1 307 329 115, 1 307 329 098, 1307329098, 1 307 329 121, 1307329121, 1 307 329 123, 1307329123, 1 307 329 124, 1307329124, 1 307 329 129, 1307329129, 1 307 329 203, 1307329203, 1 307 329 250, 1307329250, 1307329293, 1 307 329 294, 1307329294, 31213765, 31213766, 30678910, 30678911, 8E0 907 391 B, 8E0907391B, 8E0907391 B.