[C1Category("Data")]
[C1Description("RibbonItem.Tag", "User-defined data associated with the RibbonItem.")]
[TypeConverter(typeof(StringConverter))]
public object Tag { get; set; }

<C1Category("Data")>
<C1Description("RibbonItem.Tag", "User-defined data associated with the RibbonItem.")>
<TypeConverter(GetType(StringConverter))>
Public Property Tag As Object