🍎➕🍏 Essential system software for your nostalgic early compact Macintosh. - Macintosh 128K can run the pre-release versions through System 3.0 (all using 400k disks). - Macintosh 512K with a 400k floppy drive can run System 1.0 through System 3.0, the System 3 HD 20 Startup if it has a hard disk, and the PATCHED versions of Systems 4.2 or 4.3 (all using 400k disks).
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