16x20x4 (3 5/8) Pleated Air Filters MERV 13 Plus Carbon 1 Pack nutrient-combo 50 Pint is 4

50 Pint is 4

Vinegar (Acetic Acid) – Contributes to rapid desiccation of plant tissue

• 20 ml single-use Bluelab Solution Sachets

Repeat this process again several days later

we may turn yellow in protest

16x20x4 (3 5/8) Pleated Air Filters MERV 13 Plus Carbon 1 Pack nutrient-combo 50 Pint is 4Important 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 16x20x4 filter