Honeywell Home Media Air Filter 16 x 20 x 4 MERV 13 (1 pk)
- Efficiency ratings are based on American Society of Heating, Refrigerating and Air-Conditioning Engineers Standard 52.2 1999.
- Efficiency ranges are defined for small particles, E1=0.3 to 1.0 microns.
- and large particles, E3=3.0 to 10.0 microns.