20x20x4 (3 5/8) Furnace Air Filters MERV 12 Pleated Plus Carbon 1 Pack trays Spraying once or twice a

Spraying once or twice a week will suffice for correcting nutrient deficiencies as well as adding an extra boost to plant health

Fits Daystar (DAUN)

Tarnished Plant Bug)

• Remains stable over the planting cycle

At the heart of both these systems is the new and improved PHB4030 Phantom Commercial DE Ballast with USB Interface

20x20x4 (3 5/8) Furnace Air Filters MERV 12 Pleated Plus Carbon 1 Pack trays Spraying once or twice aImportant 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