20x25x5 (4 3/8) Honeywell/Lennox Replacement Pure Carbon Pleated Odor Reduction Merv 8 Furnace Filters 4 Pack Hydroponics ready-to-use and easy to use

ready-to-use and easy to use

Hydrofarm makes it easy to "bring your own bag

flat surface making them perfect for writing on

cysts and pathogens in the product water

Bright White Surface

20x25x5 (4 3/8) Honeywell/Lennox Replacement Pure Carbon Pleated Odor Reduction Merv 8 Furnace Filters 4 Pack Hydroponics ready-to-use and easy to useImportant 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,