watchOS 4.3.2 (build 15U70) is an official Apple over-the-air update for the Apple Watch Series 1 (38mm), released on 2018-07-09T17:08:06Z. The update package is 331.85 MB. This is a delta (partial) update that requires 4.2.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: f4a64b4baa7b8f62c2ebee3b17d9e6e42e734b3d.zip.