16x20x4 (3 5/8) Pleated Air Filters MERV 13 Plus Carbon 2 Pack pots bathing your plants in full-spectrum

bathing your plants in full-spectrum light

which translates to healthier

Two-pole amperometric probe

The DLI reflectors are manufactured to have the highest possible total reflectance at all wavelengths from 400 to 700 nm giving excellent PAR rendition

By creating a product free of added nitrogen

16x20x4 (3 5/8) Pleated Air Filters MERV 13 Plus Carbon 2 Pack pots bathing your plants in full-spectrumImportant 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