The secret to the Austin Air HealthMate Plus air purifier is the filter. The units are built with a pre-filter that surrounds a proprietary 3-stage filter. Featuring 60 sq. ft. of Medical-grade True HEPA filter paper that follows a layer of 15 lbs. of granular carbon and zeolite impregnated with potassium iodide. This leads to a reduction of harmful chemicals, noxious gases, VOC's, formaldehyde, odors and sub-micron particles for individuals in the most contaminated of settings. So complete, this filter is certified to remove 99.97% of airborne particles 0.3 microns or larger in size and 95% of all particles down to 0.1 microns. No other personal air cleaner comes close. This is the White replacement filter only, appropriate for the White and Standstone Healthmate Plus units. Please note, this is the replacement filter only. The Healthmate Plus Air Purifier is available separately. Replacement only requires work gloves and a Phillips-head screwdriver. While engineered to last for up to 5 years, an area having many pets, new carpeting, paint fumes, heavy smoking, urban pollution, photo studio, etc. will diminish the filter's life. Cleaner air means better sleeping. The filters help lessen night-time allergies and asthma attacks which means fewer runny noses and cases of dry mouth. Leads to better health as the device filters chemicals, gases, viruses and bacteria, allowing immune systems to strengthen as coughing, wheezing and sneezing are reduced or eliminated. Keeping the filter working great is easy. Periodically vacuum the outside of the machine, clearing away the larger and most visible particulate matter and dust.