GCZ AP404 air purifiers for allergies and asthma can refresh the air in rooms up to 3500 sq. ft, with a CADR of 307 CFM. It's a whole-house air purifier perfect for large rooms and condos. Connecting home WiFi(not 5G) to open a smart healthy living, not only can you control it with buttons and remote control, but you can also control your air purifier through voice commands and an app. 4-stage filtration H13 True HEPA filter, can capture and reduce up to 99.97% of particles as small as 0.3 microns in the air, including dust, pet dander, hair, pollen, cigarette smoke, odors, oil fume, VOC, and more. Get great relief from asthma, pet allergies, coughs, sinusitis, sneezing, and chronic allergies. To find official replacement filters on Walmart, please click here!