watchOS 5.0 (build 16R5360a) is an official Apple over-the-air update for the Apple Watch Series 3 (42mm, LTE), released on 2018-08-24T17:14:19Z. The update package is 650.45 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: ec5f1fa8396bd9cfa6251242c583e4d6e7af0b8a.zip.