Filters & Accessories Gas and Odor Reducing Air Purifier K Pre-Filter – 2 Pack, HRF-K2LEARN MORE1 Year A Pre Filter Kit For HEPA Air Purifiers For Medium Rooms, HRF-A100LEARN MORER Filter and A Pre-Filter Value Pack for HEPA Air Purifiers for Extra Large Rooms, HRF-AVRP300LEARN MOREHEPA Air Purifier R Filter and A Pre-Filter Value Pack, HRF-ARVPLEARN MOREHoneywell Gas And Odor Reducing Air Purifier B Pre Filter, HRF-B1LEARN MORE1 Year A Pre-Filter Kit for HEPA Air Purifiers for Extra Large Rooms, HRF-A300LEARN MOREOdor Reducing Carbon Type “A” Pre-Filter, HRF-AP1LEARN MOREPremium Gas and Odor Reducing Air Purifier A+ Pre-Filter, HRF-APP1LEARN MORER Filter and A Pre-Filter Value Pack for HEPA Air Purifiers for Large Rooms, HRF-ARVP200LEARN MORE