18x27x1 Exact MERV 10 Plus Carbon AC Furnace Filters 6 Pack hydro-components Multiple grades available: #2 Perlite

Multiple grades available: #2 Perlite (1/16" - 5/8" granules)

HGRES40PWC - 40 Gal Res Cover Premium White 38

N to K ratio ideal for full production cycle bloom finisher

Great quality product

it makes the sharpening process nearly effortless

18x27x1 Exact MERV 10 Plus Carbon AC Furnace Filters 6 Pack hydro-components Multiple grades available: #2 PerliteNordic Pure Custom MERV 10 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