watchOS 5.3 (build 16U5566a) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2019-07-09T17:19:27Z. The update package is 103.08 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: 02ccaded96a6d28a039999a593228d1a4f5b23c2.zip.