Small, quiet desk size. Titanium dioxide coated screen boosts UV performance. Ultraviolet bulb helps remove airborne germs, bacteria and other microorganisms. Rinsable pre-filter catches lint, pet hair and other large particles. HEPA filter traps 99.9% of dust and pollens down to 0.3 microns. Timer set for 2/4/8 hour operation cycles. Ionizer emits negative ions into the air that cling to and weigh down airborne dust, pollens and germs, making them easy for the filter to trap. Change filter indicator.