watchOS 4.3.2 (build 15U70) is an official Apple over-the-air update for the Apple Watch Series 1 (42mm), released on 2018-07-09T17:08:10Z. The update package is 158.94 MB. This is a delta (partial) update that requires 4.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 319c117505615d7ade597d14d104303784ce422f.zip.