watchOS 5.3.1 (16U600) 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 August 26, 2019 Upload Date August 22, 2019 Filename 9d18cfc3598fe218f3016fb0f133c5b58b720928.zip Filesize 1.4 GiB Identifier Watch4,3
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