watchOS 4.2.2 (build 15S5536a) is an official Apple over-the-air update for the Apple Watch (42mm), released on 2018-01-03T18:21:56Z. The update package is 65.83 MB. This is a delta (partial) update that requires 4.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 84da0fbbde480eec3bb9ccb60254bdadf66324a2.zip.