If you have the John Cooper Works Tuning Kit with the JCW Cold Air Intake kit in your MINI, this is an AFTERMARKET replacement filter.
This filter fits the JCW Intake in both the Gen 1 (R53/R52) Cooper S as well as the Gen 2 (R55/56/57) Cooper S.
Fits the following MINIs WITH the John Cooper Works Tuning Kit Cold Air Intake:
2002-2006 R53 MINI Cooper S Hatchback
2005-2008 R52 MINI Cooper S Convertible
2007-2010 R56 MINI Cooper S Hatchback
2008-2010 R55 MINI Cooper S Clubman
2009-2010 R57 MINI Cooper S Convertible
Check to make sure you have the 'cylindrical filter' and not the flat panel filter. This is not a 'conversion' kit.
A dirty air filter lowers your gas mileage. Change this filter once a year or more often if you drive in a dusty environment.