watchOS 5.0 (build 16R6364) is an official Apple over-the-air update for the Apple Watch Series 1 (38mm), released on 2018-09-12T19:18:35Z. The update package is 503.41 MB. This is a delta (partial) update that requires 5.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 702e964194aba04fb9415859f3bb37f9f03db706.zip.