watchOS 5.0 (build 16R5340g) is an official Apple over-the-air update for the Apple Watch Series 3 (42mm, LTE), released on 2018-08-06T17:12:04Z. The update package is 534.3 MB. This is a delta (partial) update that requires 4.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 1244e450322e4908d4adda0f45cc7c3d4f121f5f.zip.