watchOS 5.1.3 (16S535) 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 January 22, 2019 Upload Date January 11, 2019 Filename b4de988c2cdb429012f26a7760d01f653f380ef5.zip Filesize 1.3 GiB Identifier Watch2,6
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