watchOS 5.2.1 (build 16U5101c) is an official Apple over-the-air update for the Apple Watch Series 2 (38mm), released on 2019-04-22T17:12:38Z. The update package is 113.92 MB. This is a delta (partial) update that requires 5.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 34376ec3bb153f319d7ba1b6d725359e1787d415.zip.