watchOS 5.2 (build 16T5181f) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm, LTE), released on 2019-01-24T18:08:37Z. The update package is 419.99 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: 42f145341638bb62be4270b7306fed9051f30f22.zip.