20x20x4 (3 5/8) Furnace Air Filters MERV 10 Pleated Plus Carbon 2 Pack LUXX 200W BAR 208-277V DYNOMYCO mycorrhizal inoculants are tested

DYNOMYCO mycorrhizal inoculants are tested and proven beneficial by thousands of growers around the world

• Unlike coco you need to flush the substrate first time you use it in order to saturate the clay pebbles initially

See attached image for specs

No drainage holes

20x20x4 (3 5/8) Furnace Air Filters MERV 10 Pleated Plus Carbon 2 Pack LUXX 200W BAR 208-277V DYNOMYCO mycorrhizal inoculants are testedImportant 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