watchOS 5.1 (16R5559d) for Apple Watch Series 4 (44mm) ✗ 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 September 18, 2018 Upload Date September 14, 2018 Filename 7ad704ff12aac40d522b39e0cd41d98c62332bc0.zip Filesize 1.3 GiB Identifier Watch4,2
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