watchOS 5.1.2 (build 16S6046) is an official Apple over-the-air update for the Apple Watch Series 1 (38mm), released on 2018-12-06T18:04:11Z. The update package is 76.67 MB. This is a delta (partial) update that requires 5.1.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 95657432b49325758651528aaa20450f98d1155b.zip.