watchOS 5.1 (16R5589c) for Apple Watch Series 4 (44mm) ✗ This OTA is not signed. OTA firmwares cannot be restored to. IPSW Downloads collects them for
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Release Date October 22, 2018 Upload Date October 19, 2018 Filename 1d98882361caa54b4186d044c6b9f289b93d45df.zip Filesize 1.3 GiB Identifier Watch4,2
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