Puredry PD 20L Replacement Carbon Filter This high performance activated carbon filter removes odors, smoke, chemicals and more from the air entering the dehumidifier. A must for allergy and asthma sufferers, this filter is lab tested to trap 99.97% of harmful airborne particles, bacteria, germs and pollutants. The filter must be changed every 3-4 months, depending on the pollutants in the application area. Provide in airtight packaging. Dimensions Height, Length, Width 240*114*3 mm