watchOS 5.1.3 (16S5531a) for Apple Watch Series 4 (44mm) ✗ 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 ddca40d08c5ad004ce49a9494241626c85dbb605.zip Filesize 1.3 GiB Identifier Watch4,2
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