watchOS 4.2 (build 15S5090c) is an official Apple over-the-air update for the Apple Watch (42mm), released on 2017-11-06T18:02:56Z. The update package is 168.63 MB. This is a delta (partial) update that requires 4.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 5eaab40fe620233ba916fbba6a52397374e97cf0.zip.