20_1/2x25_1/2x1 Exact MERV 8 Plus Carbon AC Furnace Filters 6 Pack Emitters this product is non-phytotoxic and

this product is non-phytotoxic and a good way to provide calcium for growth

Water-resistant housing

Made from fresh fish from the Atlantic Ocean and contains no chemical additives

Complete control of your grow room from up to 150 ft away without wires

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20_1/2x25_1/2x1 Exact MERV 8 Plus Carbon AC Furnace Filters 6 Pack Emitters this product is non-phytotoxic andNordic Pure Custom MERV 8 Plus Carbon air filters are made based on the actual measurements so be sure to measure your current filter to get the EXACT dimensions before ordering. As with all Nordic Pure filters, the effective life of your filter depends on the environment in which you live. We recommend changing 1 and 2 filters every 30 90 days. Our 4, 5 and 6 inch thick filters could last up to 6 months. EXACT MEASUREMENT: Furnace and air condition