watchOS 5.1.3 (16S5531a) for Apple Watch Series 1 (38mm) ✗ This OTA is not signed. OTA firmwares cannot be restored to. IPSW Downloads collects them for
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Release Date December 19, 2018 Upload Date December 17, 2018 Filename 054c0805575e57adda99e5ee58665383b279fafb.zip Filesize 1.3 GiB Identifier Watch2,6
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