UNI Filter NU-3240ST - Two Stage Air Filter

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.

UNI Air Filter Red Fits 2000 Yamaha Big Bear 400 YFM400 : Unsurpassed in airflow, dirt stopping and overall performance Two-stage air filters come apart for maximum airflow and ultimatecleaning Most filters feature the Ultra Seal grease groove on the sealing surface Each fits in stock air box exactly like OEM filter Clean easily with grease-cutting dishwashing detergent; just clean, oiland reuse indefinitely .