16x20x4 (3 5/8) Pleated Air Filters MERV 7 Plus Carbon 1 Pack X Nutrients Grow Spray 1 Gal ideal for all pH testing

ideal for all pH testing

The Amazing Doctor Zymes Eliminator can be used preventively or to eliminate active infestations

Now with 15% more perlite in every bag

cleanable sediment

Begin using TundraTM at the onset of the flowering cycle and continue use through the flowering/fruiting stage

16x20x4 (3 5/8) Pleated Air Filters MERV 7 Plus Carbon 1 Pack X Nutrients Grow Spray 1 Gal ideal for all pH testingImportant 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