Genuine OEM Audi Rear Left Upper Antenna Amplifier, part number 4M8035225C. This electronic module is designed to boost the signal received by the vehicle's antenna, improving reception for radio, navigation, and other communication systems. It is specifically located in the rear left upper section of the vehicle, typically integrated into the roof or pillar structure. This compact amplifier measures approximately 0.11 meters in length and weighs 0.057 kg. Using a genuine OEM antenna amplifier ensures correct signal processing, frequency compatibility, and reliable performance for all integrated communication and entertainment systems.