watchOS 5.0 (build 16R5303d) is an official Apple over-the-air update for the Apple Watch Series 1 (38mm), released on 2018-06-19T17:36:29Z. The update package is 214.3 MB. This is a delta (partial) update that requires 5.0 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 18ea3e6bb3ab26f625f20b07c077bd2d6fc87633.zip.