iOS 9.9.13.5 (build 17F6075) is an official Apple over-the-air update for the iPhone 11 Pro Max, released on 2020-05-18T17:18:47Z. The update package is 3.87 GB. This is a full OTA update that can be applied from any compatible base version. This update is no longer signed by Apple, meaning it can no longer be applied on-device through Settings.

Payload file: 3b86be82dd8507c376eec52037a943cc9923be98.zip.