20x20x4 (3 5/8) Pleated MERV 8 Air Filters 6 Pack chillers-heaters-and-purification rugged handles with reinforced stitching

rugged handles with reinforced stitching provide portability and greater weight support

which provide a gradual ramp-up and down at both ends of your photoperiod

Enriched with mycorrhizae

"Just Coir"

20x20x4 (3 5/8) Pleated MERV 8 Air Filters 6 Pack chillers-heaters-and-purification rugged handles with reinforced stitchingImportant 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. If you are replacing a 4 3 8 depth 20x20x4 filter