watchOS 5.3 (build 16U6569) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2019-07-22T17:22:02Z. The update package is 117.39 MB. This is a delta (partial) update that requires 5.2.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 36ef577546f5c1c59e9fd82f56fe658f8c817634.zip.