21_1/2x23_5/16x1 MERV 12 Plus Carbon AC Furnace Filters 6 Pack king Additional sensors may be purchased

Additional sensors may be purchased separately (DL Wholesale product #301015)

They prefer a hole or tunnel that has been bored out by beetles or other insects

Rated life span 20

CE certified

4 RAW Phosphorus - 2 oz

21_1/2x23_5/16x1 MERV 12 Plus Carbon AC Furnace Filters 6 Pack king Additional sensors may be purchasedNordic 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