Visio Drawing Template (.vst) are vector image files created with Microsoft Visio and act as template for creating further files. These template files are in binary file format and contain the default layout and settings that are utilized for creation of new Visio drawings.
Learn more about this file format here
GroupDocs.Viewer (in GroupDocs.Viewer.dll) Version: 20.7
public static readonly FileType VST
Public Shared ReadOnly VST As FileType
static initonly FileType^ VST