watchOS 5.2.1 (build 16U113) is an official Apple over-the-air update for the Apple Watch Series 2 (42mm), released on 2019-05-13T17:16:01Z. The update package is 822.75 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: 60082af0bcf187f553e60bc7a14eb9ea8de75c09.zip.