The fog is pervasive. What air purifier is good for double eleven?

The winter is coming, and the temperature is dropping all over the country. But when you close the window, it will be stuffy, and if you don't close the window, there will be smog! In addition, the sewer smells bad, and cats and dogs at home will lose their hair, so they bought a fresh air purification system, which is different from the traditional fresh air system and needs to be installed and arranged during decoration. For me wandering in the imperial city, the cost is too high The fresh air purification system I bought is a single system, which will be very convenient even if I move and change the filter element in the future.