The ComfoAir 350/550 Filter 2-pack.
The filter replacements are for both the ComfoAir 350/550 ERV and HRV Ventilation Device.
It is recommended to order the filters in quantities of two or more so both filters in the units are replaced at the same time to ensure optimal indoor air quality in the home.
G4 Filter, MERV 8 - winter filter for supply or exhaust, or bypass filter for summer operation.
F7 Filter, MERV 13 - summer pollen filter for supply only.