watchOS 4.3 (15T5209a) for Apple Watch Series 1 (42mm) ✗ This OTA is not signed. OTA firmwares cannot be restored to. IPSW Downloads collects them for
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Release Date March 12, 2018 Upload Date March 9, 2018 Filename a88205b708cda3a26e3b316bd76c0c0e2d6e6518.zip Filesize 1.1 GiB Identifier Watch2,7
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