The secret to the HealthMate Junior is the filter. The units are built with a pre-filter that surrounds a proprietary 3-stage filter. The filters feature 30 sq. ft. of True Medical HEPA filter paper, 6.5 lbs. of activated carbon to maximize surface area and an advanced military carbon cloth placed inside the True Medical HEPA filter to capture odors and gases. By forcing air through these various filtration media 99.97% of all air borne particulate matter larger than 0.3 microns is removed while also eliminating over 3000 toxic gases and odors. No other personal air cleaner comes close. Available in Black. Over the last 10 years, HealthMate Filters have been consistently ranked #1 in the world in a number of consumer and commercial tests. 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. Better health is in the forecast as the device filters viruses and bacteria, allowing immune systems to strengthen as coughing, wheezing and sneezing are reduced or eliminated. Keeping the filter working great is easy. Just periodically vacuum the outside of the machine, clearing away the larger and most visible particulate matter and dust.