20x20x4 (3 5/8) Pleated Air Filters MERV 15 Plus Carbon 6 Pack bio soil Helps to prevent root rot

Helps to prevent root rot in cuttings without the use of fungicides or herbicides

with programmable sunrise/sunset cycles

Calcium (Ca) is a critical structural component of cell walls

Sodium Bicarbonate (baking soda)

Includes a quality UL-listed water pump with pre-filter housing to keep sprayers free from debris and preventing clogging

20x20x4 (3 5/8) Pleated Air Filters MERV 15 Plus Carbon 6 Pack bio soil Helps to prevent root rotImportant 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