watchOS 5.1.3 (16S5531a) 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 19, 2018 Upload Date December 17, 2018 Filename f3f4b592793574971d0b4eea51b6d7f49a0074c1.zip Filesize 1.4 GiB Identifier Watch4,4
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