This class creates a ribbon separator

Autodesk.AutoCAD.Customization.ElementBase
    Autodesk.AutoCAD.Customization.VersionableElement
        Autodesk.AutoCAD.Customization.CustomizationElement
            Autodesk.AutoCAD.Customization.RibbonItem
                Autodesk.AutoCAD.Customization.RibbonSeparator

Public Class RibbonSeparator
Inherits RibbonItem

public class RibbonSeparator : RibbonItem;