Mask on account numbers to let users enter 10 digits only

Hi guys,

I have written the following code and it works fine but is there any way we can display 10 underscores ( like input mask so the users will know they need to enter 10 digits??)

Code:

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Private Sub txtAccount1_Change()
Static abort As Boolean
    Static c
  If abort Then: abort = False: Exit Sub
    With txtAccount1
        c = c + 1
        abort = True
        .Text = Left(.Text, 10)
    End With
End Sub

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