watchOS 4.0 (15R5371a) for Apple Watch Series 1 (38mm) ✗ 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 28, 2017 Upload Date August 26, 2017 Filename 454bde80b4aec5e77da1dd00b7274f80b98abff7.zip Filesize 1.1 GiB Identifier Watch2,6
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