Charcoal activated cabin filter. Recommended to be replaced every 20k miles.
FITS All B6/B7 Audi A4/S4/RS4
Part #’s
4B0-819-439-C / 4B0819439 C / 4B0 819 439 C / 4B0819439C
4B2-819-441-A / 4B2819441 A / 4B2 819 441 A / 4B2819441A
4B1-819-441-A / 4B1819441 A / 4B1 819 441 A / 4B1819441A
4B0-819-439-B / 4B0819439 B / 4B0 819 439 B / 4B0819439B
