17_1/2x17_1/2x1 Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack Plant Support mushrooms and other food crops

mushrooms and other food crops

Specification: Triple washed to ensure low EC (0

12 μmol/JIngress

No Need for Cal-Mag Supplements: Rich in calcium and magnesium in the optimal 4:1 ratio

17_1/2x17_1/2x1 Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack Plant Support mushrooms and other food cropsNordic Pure Custom MERV 13 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