Camfil Air Purifier CITY is typically Swedish. It is quiet, efficient, stylish and environmentally conscious. If you compare filter you will understand why CITY is the best air purifier for offices, schools and public places. It is also very easy to use. Just ”plug and play”. Within a few hours it reduces one million hazardous particles per cubic meter. CITY is simply the best investment you can make for healthier staff and safer customers.