??? The fan for the motor direct-coupled, compact structure compact, the main advantages of this design is easy to install and easy, pumping exhaust effectiveness is good, the product has a small overall model and easy to maintain, the advantages of the system failure rate in recent years to focus on the development of the Company's products. Its made according to customer requirements can also be installed with bottom shelf, are also developed for pot cited Wind straight backward formula (C-type transmission) fan.