Where is / what is, Visual C++ "14" Runtime Libraries (x64)

I’m attempting to install SketchUp on a Windows 7 Pro PC that is not connected to the internet. I’m getting message “The following components will be installed on your machine”. What exactly is Visual C++ “14” Runtime Libraries (x64), and what URL would SketchUp go to if it were connected?

The visual libraries are needed for correct running of SketchUp.

It will attempt direct download from Microsoft servers.