ATI Cooling Fan:
SunPower and Dimmable SunPower use the same fans. Most are 3", but your best course of action is to measure the distance across the fan cover.
T5 section Only: For use the the T5 Powermodule, and T5 section of the LED Hybrid Powermodule.
LED Section Only: Only for use the LED portion of the LED Hybrid Powermodule
Sirius: Only for use on the Sirius