watchOS 4.3.1 (15T5535b) for Apple Watch (38mm) ✗ This OTA is not signed. OTA firmwares cannot be restored to. IPSW Downloads collects them for
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Release Date April 2, 2018 Upload Date March 29, 2018 Filename 4d74dd8e1c749ae9dee34a4e2c917413e8cd2318.zip Filesize 1.1 GiB Identifier Watch1,1
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