The PCAC itself is mostly made from plastic, except for the motor and the fins which are metal. Next to the motor, there is a small PCB board which is most likely for routing the power as there is a capacitor and two 3-pin power headers, one wired to the turbine motor while the other is for plugging in the 3-pin power cable. There is also a metal knob at the side to adjust the fan speed. The fin blades of the blower seems to be made of aluminium and are curved to help "catch" the air better.



Link: HardwareZoom