watchOS 5.0 (build 16R5357a) is an official Apple over-the-air update for the Apple Watch Series 3 (42mm, LTE), released on 2018-08-20T17:09:14Z. The update package is 375.29 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: 94c341494cba3b61a8eb93f525da9eeb0626489d.zip.