ULO (the OEM for BMW) have been discontinued from purchase worldwide

Chinese sensors are known to be inferior non-functioning parts

Ship-to address will be emailed after checkout on the site

non stainless imitations that sell for less

Please note: I can no longer purchase new aftermarket cases with gray buttons

OEM Die Wethje S54 / P54 "CSL" Airbox - NEW M3 Lightweight ULO (the OEM for BMW)New never used OEM Die Wethje CSL Airbox Die Wethje is the OEM manufacturer for BMW and their CSL airbox. This airbox is a variant, by Die Wethje, for the S54 CSL setup. The exact purpose of this box is unknown. With the missing unfiltered portion it is a race style (similar to the Karbonius Race), but it lacks some of the details that the P54 airbox has. This box falls in the middle of the CSL and P54. This is for the main airbox portion only. No