Hello Alex,

Thank you for your post. I have been looking into it for you and it seems there is no built-in way to achieve it. I can suggest you retemplate the XamComboEditor so it uses a XamMaskEditor in its EditTemplate and set its Mask property to {}{double:3.2}, which would provide the necessary functionality. You can start by copying its original templates to your project (you can get them form the DefaultStyles folder) and modify them of your choosing. Please note, we are making effort to ensure that all forum posts are addressed by an Infragistics expert. We believe that other community users can benefit from this thread as well.

If you have any further questions feel free to ask.