Review on 🔍 MIKKUPPA KT035 (CF10368) Cabin Air Filter - Audi A4, A6, RS4, RS6, S4, S6 - Replacement 4B0819439C by Carl Estell

As another reviewer mentioned, there is no airflow direction label so you can use the part number printed on the side and the Need to guess color of carbon layer on the bottom. (I hope I guessed right. The filter fits a lot tighter than the previous filter due to the fluffy insulation on the sides (the previous filter was just bare cardboard. The tight fit made the filter easy to squeeze when inserting, and I had to try several.) time to get it right.In my car I have finally found that only when I inert with the side with the part number label correctly installed will the filter seat properly without wrinkles and I will continue to enjoy good cabin air.