watchOS 5.1.3 (16S535) 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 January 22, 2019 Upload Date January 11, 2019 Filename 3c5238738fd5d3c7584e7fc00223f36330cc140e.zip Filesize 1.4 GiB Identifier Watch4,3
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