The duct inline fan produced by Taeil blower is the middle type of centrifugal type and axial type wing, which is the most recently developed wing type. In addition, the general centrifugal wing is a fixde wing type or a variable wing structure which is advantageous of the axial wing of the wing. It is possible to meet various customer's specifications form the motor direct drive fan. It is easy to install because the fan casing is rectangular, and it can be operated in the air flow when it is made in the form of a multi-layer structure. It is mainly used for parking lot supply, exhaust system, machinery room and electric room ventilation facility.