What are the common bathroom exhaust fan sizes?

The Exhaust Fan are  playing a important role in the bathroom. Its purpose is to realize the ventilation treatment of the bathroom, maintain a good ventilation for the bathroom, make the bathroom not wet, and bring convenience to people's bathing and many other lives. Since there are many kinds of bathroom exhaust fans on the market, the size of the bathroom exhaust fan also means that there are many, and our owners can choose different types of exhaust fans according to their different needs. Currently there are three kinds of popular on the market, then come with me to look at the bathroom exhaust fan size and specification standards.