The Medify Air MA-25 filter has three layers of filtration: pre-filter, H13 True HEPA, and active carbon composite for odors. It removes up to 99.9% of particles down to 0.1 microns while catching pollen, dust mites, mold spores, and other tiny airborne particles. This long-lasting filter has a life of 3 to 4 months or 2,500 hours.