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High Efficiency & Pre-Filter (part #2521) for the BISSELL® air400 Air Purifier, Series 24791.
Follow these instructions for filter replacement:
- Make sure the Air Purifier is turned OFF and unplugged before replacing the filters
- Each filter has blue easy pull tabs. The tabs should face outward.
- Insert activated carbon filter before inserting High Efficiency + Pre-Filter.
- The Pre-Filter attached to the High Efficiency filter should face outward.
NOTE: Filter life varies based on run time and existing air conditions. It is recommended to replace both the High Efficiency + pre-filter and activated carbon filter once every six months.