%VCToolsInstallDir%

Subdirectories:

• atlmfc
• bin
• crt, below which is src/vcruntime, the source of the VC specific parts of the CRT.
• include
• lib
• vcperf

The version number that is included in %VCToolsInstallDir% can be found in a file like C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\Microsoft.VCToolsVersion.default.txt.