20x20x4 (3 5/8) Pleated MERV 12 Air Filters 6 Pack rockwool Soil Activator will solubilize phosphorus

Soil Activator will solubilize phosphorus and improve micronutrient availability to help boost yields during flowering and fruiting cycles

It’s also highly resistant to rips

• Zeaxanthin

Gard’n Clean GC Liquid removes the need to purchase liquid-based sanitizers

20x20x4 (3 5/8) Pleated MERV 12 Air Filters 6 Pack rockwool Soil Activator will solubilize phosphorusImportant 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