watchOS 5.1.3 (16S5523a) 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 December 10, 2018 Upload Date December 5, 2018 Filename d878d0587788f47a9a7abbfbdb6c9459c17dca44.zip Filesize 1.4 GiB Identifier Watch4,4
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