Zehnder ComfoAir 350/550 Filter Set, ISO Coarse / ISO ePM1 (G4 / F7), 2 pcs bathroom-fans-discreet-view-all It has 10 interior and

It has 10 interior and exterior pockets

The fan has a a 3year warranty

30 or 40 minutes

Airflow DV150SE Ventilation Unit filters 2 x G4

Zehnder ComfoAir 350/550 Filter Set, ISO Coarse / ISO ePM1 (G4 / F7), 2 pcs bathroom-fans-discreet-view-all It has 10 interior andIdeally, filters should be inspected monthly and given a light vacuum to remove dirt and debris. Filters will eventually become blocked with residual debris and should then be replaced. Generally, blocking will occur every 6 12 months depending on the location (near busy roads or inner city areas tend block more quickly than remote country settings). To see the Zehnder Filter fiting video on youtube please select: Comfo Air 350 Filter video Zehnder P