Lenoxx - Air treatment is heavily influenced by the extreme weather conditions of bushfires and floods. This puts a strain on asthma and allergies, causing breathing difficulties. This Air Purifier Filter 18.6cm x 14.2cm for the Air Purifier with CADR 170m/h will prevent the interior risks of poor air quality. The filter replacement indicator will illuminate on the touch screen of the air purifier and an increased operating noise coupled with decreased airflow will signal it is time to change out the size 18.6cm x 14.2cm HEPA filter. Changing the filter is as simple as twisting open the bottom of the air purifier and swapping out the filter. Always ensure the packaging is removed first before inserting the filter into the air purifier. Its time to finally breathe easy with our replacement filters for our air purifiers.