20x25x4 (3 5/8) Furnace Air Filters MERV 12 Pleated Plus Carbon 2 Packs veg-and-bloom alarm alerts

alarm alerts

The porous material is reinforced with high-quality bonded-polyester thread and is available in black or tan to accommodate your growing environment

The fan can run continuously or on a timer to start and stop when you need it to

Lower nitrogen levels help reduce stem elongation and strengthen budding areas

Contains Non Plant Food Ingredient Humic Acid

20x25x4 (3 5/8) Furnace Air Filters MERV 12 Pleated Plus Carbon 2 Packs veg-and-bloom alarm alertsImportant 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 20x25x4 filter