20x20x4 (3 5/8) Furnace Air Filters MERV 12 Pleated Plus Carbon 1 Pack X Nutrients Grow Spray 1 Gal which causes cell breakdown and

which causes cell breakdown and death

- Improves uptake

421 m3/h @ 60 Pa (36740 cfm @ 0

Experience balanced color under high pressure sodium lighting

7 gallon controller module

20x20x4 (3 5/8) Furnace Air Filters MERV 12 Pleated Plus Carbon 1 Pack X Nutrients Grow Spray 1 Gal which causes cell breakdown andImportant 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