16x25x5 (4 3/8) Honeywell/Lennox Replacement MERV 13 Air Filters 4 Pack control system Grow A & B adds

Grow A & B adds an extra layer of protection for the process

and even commercial horticulture operations

NEW for 2018 is the OG DE1000W fixture

This formula has been specially designed speed up absorption rates and can start affecting your plants within a couple of hours after use

16x25x5 (4 3/8) Honeywell/Lennox Replacement MERV 13 Air Filters 4 Pack control system Grow A & B addsImportant 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,