watchOS 5.3 (build 16U5558b) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2019-06-24T17:24:51Z. The update package is 82.3 MB. This is a delta (partial) update that requires 5.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 6b11d02bc8600518e6dc7f2bd4e01ad650649f55.zip.