watchOS 5.2.1 (build 16U5079d) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2019-03-28T17:10:55Z. The update package is 442.78 MB. This is a delta (partial) update that requires 5.1.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: a38fb44d413626b92b3d405d34d1c0c66c872cd3.zip.