This carbon filter is for use with NXT120 and NXT120C dehumidifiers. It is a larger filter specifically for the NXT120 dehumidifiers and they measure 14" x 14". It sits behind the pre-filter on your Watchdog Crawl Space Dehumidifier. It is used as a replacement filter for the standard MERV-10 filter that is included with your dehumidifier. A carbon filter is effectively removes dirt and dust particles as well as odors from the air. It is recommended that the filter be changed about once a year. It is not washable.
The N-1203 comes in a 3 pack.