21x27x1 Trane Replacement MERV 13 Plus Carbon AC Furnace Filters 6 Pack Promote * High precision humidity sensor

* High precision humidity sensor

We have taken CMH technology and increased its operational efficiency

Maintains airflow efficiency by creating a seamless connection between two different sized duct openings

a food processing plant

21x27x1 Trane Replacement MERV 13 Plus Carbon AC Furnace Filters 6 Pack Promote * High precision humidity sensorNordic Pure Trane Replacement MERV 13 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