The strong 6 stage purification process captures 99.97 percent 0.3 micron particles and ultra-fine particles as small as 0.02 microns (over 100 times smaller than PM2.5) Filters common allergens, dust, dust mites, pollution, bacteria and viruses (including H1N1) Long lifetime of up to 2 years depending on usage and pollution level Easy-to-install DIY (do it yourself) filter