watchOS 5.0.1 (build 16R381) is an official Apple over-the-air update for the Apple Watch Series 1 (42mm), released on 2018-09-27T20:08:33Z. The update package is 728.56 MB. This is a delta (partial) update that requires 4.3 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: d375b21321074b83fd83fa3e47d91050b0f95082.zip.