: If you are trying to install on an older machine, tools like the macOS High Sierra Patcher help you download a clean copy from Apple servers safely. macOS High Sierra - App Store - Apple
Files described as "exclusive" or specific to the .RDR format are usually found on community forums like Reddit or specialized tech blogs. How to open RDR file (and what it is) - File.org
The RDR version is exclusive and can only be downloaded by authorized Apple personnel. However, we've managed to provide a comprehensive guide on how to download and install the RDR version of macOS High Sierra 10.13.5.