watchOS 5.1.2 (build 16S5042a) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm), released on 2018-11-07T21:15:01Z. The update package is 749.94 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: 9e3cc93ec11d2a8a4d6861b0b864a2d0174f8725.zip.