iOS 13.4.5 (build 17F5044d) is an official Apple over-the-air update for the iPhone 6s, released on 2020-04-15T17:16:14Z. The update package is 184.33 MB. This is a delta (partial) update that requires 13.4.5 already installed. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 5d43d79bd2a6dce21e8cc76dc6bfb34a96927640.zip.