20x25x5 (4 3/8) Lennox X6673_X6675 Replacement MERV 10 Air Filters 4 Pack Chemicals Day and night setpoints adjustable

Day and night setpoints adjustable from 20% to 90%

simply empty

which effectively “prunes” them by stopping their growth

two on the FLT48240)

as the earthworms burrow

20x25x5 (4 3/8) Lennox X6673_X6675 Replacement MERV 10 Air Filters 4 Pack Chemicals Day and night setpoints adjustableImportant Note: Almost ALL furnace filters have a different "actual size" than the nominal size printed on the air conditioner filter. It's best if you measure your air filter for the EXACT size and compare it to our "Actual Size" and then you can be sure your A C air filter fits! With the 4" and 5" air filters there is a wider variance between the nominal and actual size depending on the manufacturer. We also carry 4 7 8 and 5 1 4 inch depth filters,