watchOS 4.3 (build 15T212) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2018-03-29T17:08:08Z. The update package is 665.19 MB. This is a delta (partial) update that requires 3.2.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 06ffd2cd4eaf7513b6d6e6e4b685846bf8325d84.zip.