watchOS 4.2 (build 15S5090c) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm, LTE), released on 2017-11-06T18:03:40Z. The update package is 179.71 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: 1e3b75c1b0b3e9bd91a92447d5eb94e89bec45b1.zip.