Yes, as Jesper says, it's something that was used before v9. The xml file in the zip file can be added to a nuget package and then installed, it's described in this documentation: https://our.umbraco.com/documentation/Extending/Packages/Creating-a-Package/#custom-package-migration I suspect you're trying to get content from one site to another one, in which case I'd recommend checking out uSync (https://our.umbraco.com/packages/developer-tools/usynccontentedition/) to help with that.