K&N Air Filter BMW X3M X4M

Expert's advice:

The K&N's replacement air filters for the BMW X3M and X4M F97/F98 are designed to increase horsepower and acceleration while providing excellent filtration. The filters are washable and reusable and are custom designed to fit into your existing factory air box. Their drop-in design means adding performance is simple. With most vehicles, you simply remove the disposable air filter and replace it with a K&N. This will be the last air filter your vehicle will ever need.

Mark Hendrikx - Automotive engineer at Mosselman