16x20x4 (3 5/8) Pleated MERV 7 Air Filters 2 Pack Travel Bags & Backpacks The LT1 controller has an

The LT1 controller has an intuitive

Root mass was noticeably larger and plants handled stress much better than previous runs

tool-free for cleaning

and CO2 with the Timer Control module the DSP-1

and lid for easy access to your nutrient solution

16x20x4 (3 5/8) Pleated MERV 7 Air Filters 2 Pack Travel Bags & Backpacks The LT1 controller has anImportant 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