"HOLMES" AIR PURIFIER Slim tower design Quiet operation modular Filter system booster assists in particle removal HEPA-type filter with Arm & Hammer(R) baking soda Particle removal: 0.3 microns Room coverage: 180 sq. ft. (12 x 15 size room) Removal rate per hour: 116 x number of speed settings 2 filter change indicator Replacement filter modelno.HAPF30PDQ-U (Ace no. 6091318) Requires 2 filters Black Boxed