16x20x4 (3 5/8) Furnace Air Filters MERV 10 Pleated Plus Carbon 1 Pack Grow1 5' Steel Stake Helps prevent stress in plants

Helps prevent stress in plants caused by either irregular watering or overwatering

And many more

Use Encarsia formosa to control Greenhouse Whitefly (Trialeurodes vaporariorum)

GroEzy Cultivation Blocks

16x20x4 (3 5/8) Furnace Air Filters MERV 10 Pleated Plus Carbon 1 Pack Grow1 5' Steel Stake Helps prevent stress in plantsImportant 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