This 2-in-1 Leitz fine dust replacement filter for the Z-1000 air purifier consists of a fine dust filter and a carbon pre-filter. The carbon filter captures the larger dust particles and the fine dust filter subsequently captures the smaller particles, down to 0.3 microns. Thanks to 360-degree filtration, the air in your room will be filtered in all directions. This combination filter has been developed to filter microscopic particles, allergens, volatile organic compounds and odourous gases from the air.