watchOS 4.1 (build 15R5823c) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2017-09-27T16:59:16Z. The update package is 276.3 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: 4e0fb587bfce79af79c05b2c3ec7f6e50ab88570.zip.