As long as it physically fits it is the correct one. The clamshells shipped with yo-yo adaptors. The newer adaptors use a smaller form factor. Though just because it fits does not mean its working....
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PB G4 15" 1.2ghz - Pismo G3 400 mhz - iBook G3 500 "Jukebox"
"SawSmurf" G4 500 - Quicksilver G4 Dual 1ghz modding...