Download of Apple PowerBook Firmware 4.2 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. This free software for Mac OS X is an intellectual property of Apple. We recommend checking the downloaded files with any free antivirus.
From the developer:
The PowerBook Firmware Update 4.2.9 will only run on 550MHz or 667MHz PowerBook G4 computers running Mac OS 9.1 or later from a local drive. If you are using Mac OS X you must boot from a local Mac OS 9.1 writeable partition (not a CD, or network disk) prior to following the update instructions.
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