This combination filter is made of several layers of filtering technology. photocatalyst and charcoal filter utilize titanium dioxide, which is activated in the uv-c light to decompose odor molecules caused by smoking, cooking and pets. also prevents the growth of bacteria, germs and mold. a true hepa filter captures 99.99% of airborne particles such as dust mites, debris, mold spores, pollens and pet dander. pre-filter captures large dust particles, lint and pet hair. fits the following models: ac5000.