12_3/4x20_3/4x1 Exact MERV 14 Plus Carbon AC Furnace Filters 6 Pack pest-and-disease-control 2 sachets each of pH

2 sachets each of pH 4

A duct filter box designed for use with inline fans to circulate fresh air and block dust and odors

Industrial-Scale Air Purification – Handles up to 10

Indoor/outdoor plants

Best Par Maintenance

12_3/4x20_3/4x1 Exact MERV 14 Plus Carbon AC Furnace Filters 6 Pack pest-and-disease-control 2 sachets each of pHNordic 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