Actually the default EditType for xamNumericEditor is double. The default mask for a double is just "{double}" which defaults to having 9 integer places and the number of fraction places being determined by the NumberDecimalDigits of the culture used. If you want to register a different mask for double you can use the XamMaskedEditor.RegisterDefaultMaskForType static method. The available tokens are listed on this page - http://help.infragistics.com/Help/NetAdvantage/WPF/2008.1/CLR3.X/html/xamEditors_Masks.html.