20x21_1/2x1 Exact MERV 10 Plus Carbon AC Furnace Filters 6 Pack commercial-greenhouse-fixtures Perfect for 4’x4’ vegetative coverage

Perfect for 4’x4’ vegetative coverage at 18”and 3’x3’ flowering coverage at 6”-12”

and helps dry fabrics faster

perimeter and spot treatments as well as fogging applications

ETL-listed

Contains AC Infinity axial fans ACX-FD8025(B)05W5 which meet UL-507 standards for safety under Underwriters Laboratories certificate E503903

20x21_1/2x1 Exact MERV 10 Plus Carbon AC Furnace Filters 6 Pack commercial-greenhouse-fixtures Perfect for 4’x4’ vegetative coverageNordic 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