Thank you for your interest.
In the current version of RadCommandBar our masked edit box is not in the list of default items. There is a CommandBarHostItem that can host any RadElement, but it has no design-time support yet. After you add the host item, you can set the hosted element by code as it is shown below:
commandBarHostItem1.HostedItem = radDateTimePicker;
Feel free to ask if you have any further questions.
the Telerik team
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