The Membrane Solutions MS18 Air Purifier is perfect for large rooms up to 825 sq/ft. It features a 4-stage filtration system, including a washable pre-filter, blue silver ion filter, H13 True HEPA filter, and activated carbon filter that effectively removes 99.97% of particles as small as 0.3 microns and air pollution PM 2.5. With 3 fan speeds, sleep mode, timer 2/4/8 hrs, and filter replacement indicator, it's an ideal choice for smokers, pet owners, and allergic groups. The physical keys, blue night light, and quiet sleep mode make it user-friendly. The MS18 is CARB-certified and has a filter service life of 6-8 months. US stock with fast shipping.