watchOS 3.1.3 (build 14S960) is an official Apple over-the-air update for the Apple Watch (42mm), released on 2017-01-23T18:02:18Z. The update package is 583.14 MB. This is a delta (partial) update that requires 2.2 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 5b0a94313bcc8afe5c2e7e09df39e4783dbff6e6.zip.