Muffler (sus φ80x4tip)
Part no.: 4101-21111
Application: F11(touring) 523i / N52B25
Discription:

Material: stainless steel（SUS304）
Main pipe: φ60.5mm
Tail pipe: φ80mm / 4 tip
Contents: rear silencer (not come with diffuser on the picture)
Installation: needs to cut factory exhaust and rear bumper.
Control valve: not available.

Approved: JQR (Meet Japanese standard)

Noise level for reference
(It might be different depending on the condition)
84dB at 4725 rpm