watchOS 4.2.2 (build 15S542) is an official Apple over-the-air update for the Apple Watch Series 1 (42mm), released on 2018-01-19T18:09:05Z. The update package is 145.04 MB. This is a delta (partial) update that requires 4.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 22def293bdc34fc5d5a0727fb984333ff5cf107f.zip.