Left hand cooling fan for 1GHz, 1.2GHz, 1.33GHz, 1.5GHz & 1.67GHz (1280x854 screen) models of the 15" Aluminium PowerBook G4. This part will not fit the dual layer Superdrive version (1440x960 screen) of the 1.67GHz PowerBook. This fan mounts in the main processor heat sink and is essential to the safe operation of the PowerBook.