watchOS 5.1 (16R591) 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 October 30, 2018 Upload Date October 22, 2018 Filename 27fc6f677188316dc9e9803f32eb8324d544166f.zip Filesize 1.4 GiB Identifier Watch4,4
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