watchOS 5.1 (16R5589c) for Apple Watch Series 4 (40mm) ✗ This OTA is not signed. OTA firmwares cannot be restored to. IPSW Downloads collects them for
potential future use. They might also be useful if you're doing research.
Release Date October 22, 2018 Upload Date October 19, 2018 Filename 3547c96155b115374dca8dddcf8faa101f343cbb.zip Filesize 1.3 GiB Identifier Watch4,1
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