21x23_1/4x1 Exact MERV 7 AC Furnace Filters 6 Pack bio soil Adjust PPM higher in later

Adjust PPM higher in later stages of the bloom cycle to desired strength

• 4200K lamp included

you can run a top watering system that is virtually clog-free

Each layer of material is bonded to polyurethane for strength and durability and has a inner layer of insulation to prevent conductive heat flow

21x23_1/4x1 Exact MERV 7 AC Furnace Filters 6 Pack bio soil Adjust PPM higher in laterNordic Pure MERV 7 Pleated AC Furnace Air Filters provide exceptional filtration for both home and commercial environments. Each time air passes through a Nordic Pure pleated furnace air filter, lint, dust, pollen, bacteria, pet dander, dust mites, mold spores and other contaminants are removed. MERV 7 furnace filters are comparable to HVAC filters with the rating of MPR 600. While different companies use different scales to measure the air filters