Universal Pre-Filter, 8.37 x 8.5

Helps reduce common household odors. In addition, helps maximize the HEPA filter life. Should be replaced approximately every 3 months. Air Purifier Filter Type: Carbon; Air Cleaner Compatibility: 17000 Series; 18150 Series; 50250 Series; 40200 Series; Width: 8.37″; Depth: 2.87″.