watchOS 4.3 (build 15T5199f) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2018-03-06T18:08:06Z. The update package is 337.39 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: 5923e939c3718155dddbb17de59a423f7f6ddb5a.zip.