Genuine OEM Audi Exterior Mirror Mounting, part number 4K1857409F9B9. This critical component serves as the structural base and internal frame for the exterior side mirror assembly. It is positioned on the left side of the vehicle, securing the mirror to the door. The mounting is finished in Satin Black (9B9). Choosing a genuine OEM mirror mounting ensures precise alignment, proper electrical connections, and structural integrity for the entire mirror assembly, crucial for safety and functionality.