watchOS 5.0 (build 16R5340g) is an official Apple over-the-air update for the Apple Watch Series 1 (38mm), released on 2018-08-06T17:11:49Z. The update package is 484.37 MB. This is a delta (partial) update that requires 4.3.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: feee8d3cf79fe18180ddc6d676a7f4df2e536515.zip.