Different grades of filter provide different levels of filtration based on the size of particles that they remove from the airstream:

 

• ISO 45% (G3) Course will provide the minimum required filtration

• ISO ePM10 50% (M5) will remove smaller particles, including pollen

• ISO ePM2.5 70% (F7) provides high level of filtration, removing tiny PM2.5 particles often found in exhaust fumes

 

Higher grade filters are only required on the intake side of the system