watchOS 5.1.1 (build 16R6600) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm, LTE), released on 2018-11-05T18:06:06Z. The update package is 174.41 MB. This is a delta (partial) update that requires 5.1 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: c8d7f6500dc78af20633cafc2bd25b7e6eee4a32.zip.