UNI AIR FILTERS. The principal of how foam air filters work is simple: Open Cell polyurethane foam is wetted with specially developed filter oil. The sticky filter oil is suspended in the path of the dirty air on the strands of the web-like cell structure of the foam. This makes it impossible for the dirt to pass through the strands. As the outer strands become loaded with dirt particles, the wetted strands down stream start trapping dirt, allowing the entire thickness to be utilized. This prevents surface loading or air restriction for 80% of the surface life of the air filter element. When the filter is sufficiently dirty it can be easily washed, re-oiled and re-used.Additonal Fitment:2008-2008 BOMBARDIER / CAN-AM ATV 500 RENEGADE2007-2008 BOMBARDIER / CAN-AM ATV 800 RENEGADE EFI2006-2008 BOMBARDIER / CAN-AM ATV 800 OUTLANDER2007-2009 BOMBARDIER / CAN-AM ATV 500 OUTLANDER2006-2009 BOMBARDIER / CAN-AM ATV 650 OUTLANDER