watchOS 5.1.3 (16S5535a) for Apple Watch Series 4 (44mm, LTE) ✗ 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 January 7, 2019 Upload Date January 4, 2019 Filename d03b0c5bb52ae0794522bc2bce34c2c872053336.zip Filesize 1.4 GiB Identifier Watch4,4
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