Cabin air filters cleans the air coming into the interior from the HVAC system. Failure to change your filter can lead to added stress and impact on the overall heating, ventilation and air conditioning system. Efficient cabin air filters are not only essential for a functioning A/ C system, but are also vital to driver and passenger comfort and safety against external contaminants. Cabin air filters also prevent dust, bacteria, pollen and other contaminants from entering the vehicle's ambient air to improve the occupant's comfort.