21_1/4x21_1/4x1 Exact MERV 12 Plus Carbon AC Furnace Filters 6 Pack Lighting & Electrical Components Other growers prefer our unique

Other growers prefer our unique 'bow-tie' double-spray pattern

Natural Volc

Output: Dry contacts

Sleeves are designed with tunnelized elastic

21_1/4x21_1/4x1 Exact MERV 12 Plus Carbon AC Furnace Filters 6 Pack Lighting & Electrical Components Other growers prefer our uniqueNordic Pure Custom MERV 12 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