21x23x1 Exact MERV 8 AC Furnace Filters 6 Pack eligible-for-discount Compatible with 120V controllers and

Compatible with 120V controllers and timers

use 3 or 4 releases at 2 weeks intervals

Raised bottom and unique multi-drainage holes and slits for optimum aeration of the root zone

using 35% less power than a 1000W DE fixture

Contains natural pyrethrins widely used in organic growing because of its rapid breakdown

21x23x1 Exact MERV 8 AC Furnace Filters 6 Pack eligible-for-discount Compatible with 120V controllers andNordic Pure MERV 8 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 8 furnace filters are comparable to HVAC filters with the rating of MPR 800. While different companies use different scales to measure the air filters