Priority Property
Returns or sets the priority of a command bar control. A control's priority determines whether the control can be dropped from a docked command bar if the command bar controls can't fit in a single row. Read/write Long.
Remarks
Valid priority numbers are 0 (zero) through 7. A priority of 1 means that the control cannot be deleted from a toolbar. Other priority values are ignored.
The Priority property is not used by command bar controls that are menu items.
Example
This example moves a control and assigns it a priority of 5 so that it will likely be dropped from the command bar if the controls don't all fit in one row.
Set allcontrols = CommandBars("Custom").Controls
For Each ctrl In allControls
If ctrl.Type = msoControlComboBox Then
With ctrl
.Move Before:=7
.Tag = "Selection box"
.Priority = 5
End With
Exit For
End If
Next