macOS 12.3.1 (21E258) for iMac 24-inch (M1, Four Ports, 2021)

iMac21,2 ipsw
iMac21,2 ipsw

Identifier: iMac21,2 Board 1 BoardConfig: J457AP Platform: t8103 BDID: 0x2A CPID: 0x8103

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