Genuine OEM Audi Charcoal Cabin Air Filter, part number 4B0819439C. This filter is crucial for maintaining air quality inside the vehicle by trapping airborne particles and absorbing odors. It is typically located within the HVAC system, filtering air before it enters the passenger compartment. Weighing 0.477 kg and measuring 0.3 m in length, this filter features activated charcoal media. A genuine OEM cabin filter ensures optimal filtration efficiency and proper airflow, protecting occupants and the HVAC system.