watchOS 4.3.2 (build 15U5069a) is an official Apple over-the-air update for the Apple Watch Series 3 (42mm, LTE), released on 2018-06-25T17:13:19Z. The update package is 368.94 MB. This is a delta (partial) update that requires 4.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 54e589c8d7fa082aec6d9fd8f417a46a2f3f49e1.zip.