16_1/2x21_5/8x1 Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack grow-light-ballasts and higher yields

and higher yields

the entire microbial matrix begins to work in concert to optimize plant growth

In their search of the perfect piece of fruit to lay their eggs in

3 - 4 mm long

16_1/2x21_5/8x1 Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack grow-light-ballasts and higher yieldsNordic 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