Apple Pro Speakers Harmon Kardon M6531 for iMac G4/PowerMac G4 only with a 2.5-mm Apple Pro Speaker minijack connection. In good condition. These Apple Pro Speakers were manufactured in 2003. Their design was based on the G4 Cube's spherical speakers but with a new digital audio system, plastic grilles and white rubber/silicone surrounds with a proprietary minijack that provided both power and audio.
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