watchOS 5.1 (16R5559d) for Apple Watch Series 4 (40mm, 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 September 18, 2018 Upload Date September 14, 2018 Filename e20d9f04b046416303a3e75b76edb4f05dae530e.zip Filesize 1.4 GiB Identifier Watch4,3
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