watchOS 4.3.1 (build 15T567) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2018-05-29T17:08:50Z. The update package is 696.72 MB. This is a delta (partial) update that requires 3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: a617a3f6c6115045687957dc2037c1afa5ef888a.zip.