watchOS 5.1.2 (build 16S6046) is an official Apple over-the-air update for the Apple Watch Series 3 (42mm, LTE), released on 2018-12-06T18:04:34Z. The update package is 98.35 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: 77512904567e6d48f24dfc4f0dfb6b8c15ba1071.zip.