16x20x4 (3 5/8) Pure Carbon Pleated Odor Reduction Merv 8 Furnace Filters 2 Pack X Nutrients Grow Spray 1 Gal Injection capabilities of 1:100 to

Injection capabilities of 1:100 to 1:20

Recommended for use with: Phresh & Black Ops Carbon Filters

Designed to withstand the knocks

Allow flowers to dry until outer leaves easily flake off when gently rubbed

The nutrients in Mag-Pro are immediately available

16x20x4 (3 5/8) Pure Carbon Pleated Odor Reduction Merv 8 Furnace Filters 2 Pack X Nutrients Grow Spray 1 Gal Injection capabilities of 1:100 toImportant 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