watchOS 5.1 (16R5589c) 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 October 22, 2018 Upload Date October 19, 2018 Filename 6b0015532ef267e9c93063c9ffea07034c71aa3c.zip Filesize 1.4 GiB Identifier Watch4,3
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