watchOS 4.2 (build 15S5100a) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2017-11-13T18:03:53Z. The update package is 160.96 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: f55424109d8c8c02a57f5070395ba0c683f34e01.zip.