This enumeration is used by the PrinterSettings.Duplex property to define the double-sided printing mode.
public enum Duplex { Simplex = 1, Vertical = 2, Horizontal = 3, Default = -1 }
System.Object System.ValueType System.Enum(System.IComparabl, System.IFormattable, System.IConvertible) Duplex
PrinterSettings.Duplex