17_1/2x17_1/2x1 Exact MERV 14 Plus Carbon AC Furnace Filters 6 Pack biological fertilizer Special features of the E-500

Special features of the E-500 includes: the unit works in areas up to 500 cubic feet

stable running

and a data logger which shows the minimum and maximum pH recorded

| Red = 420

sweeteners

17_1/2x17_1/2x1 Exact MERV 14 Plus Carbon AC Furnace Filters 6 Pack biological fertilizer Special features of the E-500Nordic Pure Custom MERV 14 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