watchOS 4.2.2 (build 15S6542) is an official Apple over-the-air update for the Apple Watch Series 1 (42mm), released on 2018-01-19T18:09:11Z. The update package is 43.65 MB. This is a delta (partial) update that requires 4.2.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 6fc3d0358522e97e3a209315b7961575b5c2c195.zip.