Please notice:
If you have normal bmw exhaust from factory (no m performance exhaust system) you need between pipes, part number 18302287043.
Cost about 60 euro extra! You need also set of chrome exhaust tips from the m performance exhaust system to install the diffuser.
Cost about 278 euro (chrome)!
Fits not for cars with trailer coupling (S235A) or rear carrier (SZEEA)!