DESC: This HEPA is warm rolled to prevent cracking at folds and laser-tested to ensure integrity. The pre-filter traps larger particles to prolong the life of HEPA and carbon filters. This pre-filter has two anti-microbial filters to suppress the growth of microorganisms and is easy to clean or change. This black Air Purifier also features baked-enamel housing that ensures no harmful vapors are released, four casters for easy maneuverability, and cylindrical shape that maximizes airflow.