KDiff3 as external tool for compare/merge?

I'd like to use KDiff3 as the compare and merge tool in Visual Studio 2017. Is this possible, and if so, how? I've googled but haven't found which arguments to use for the compare and merge operations in Visual Studio.

The Visual Studio settings for external tools are under:

Tools > Options > Source Control > Visual Studio Team Foundation Server > Configure User Tools

Thanks!