20x20x5 (4 3/8) Honeywell/Lennox Replacement Pure Carbon Pleated Odor Reduction Merv 8 Furnace Filter 1 Pack special-order Plug refills available to ensure

Plug refills available to ensure you never have to buy more equipment

It can be used in hydroponic applications of all kinds

It also contains a 15-amp circuit breaker with easy-reset switch built in to prevent hazardous circuit overloads that could damage equipment

-Only the highest quality Monofilament screens & materials selected-Guaranteed micron accuracy-Triple stitched with nylon bonded thread-Removable-Washable screens are easy to load

Calibration: Solution Nutradip EC/PPM

20x20x5 (4 3/8) Honeywell/Lennox Replacement Pure Carbon Pleated Odor Reduction Merv 8 Furnace Filter 1 Pack special-order Plug refills available to ensureImportant 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. We also carry 4 7 8 and 5 1 4 inch depth filters,