It really doesn't matter what OEM input harness you're buying if your car had the OE D1S HID system from Valeo. However, if your car came stock with halogen, then you want the harness for an H1 OEM input. The OE input in halogen cars will plug to the OE input for the halogen low beam bulb. In the case of cars with HID, we have to find a way to wire the harness to the OEM input that comes from the fuse box.