Creating Borders, xlMedium not working|VBA & Macros|Excel Forum|My Online Training Hub

I created the below macro today.  Going through it, if I choose xlThin or xlThick for my thickness it works fine, if I choose xlMedium it gives an "Unable to set the Weight property of the Border Class", and I can't figure out why.  The macro lives in my PERSONAL, and I've been testing it on a blank sheet, so no example workbook is attached.  Any help would be appreciated.

Sub BorderChooser()
'in Formatting Tools
Dim Area As String
Dim Style As String
Dim Thickness As String

Area = InputBox("All Choices work with your Entire Selection." & vbCrLf & vbCrLf & _
            "Typing A creates a Border around it all." & vbCrLf & _
            "    C  creates a Border around each Column." & vbCrLf & _
            "    R  creates a Border around each Row." & vbCrLf & _
            "    U  creates top and bottom borders for each row.", "How are we bordering?")
    If StrPtr(Area) = 0 Then Exit Sub   'User Canceled
Style = InputBox("How Thick do you want your lines?" & vbCrLf & _
                "Enter T for Thick, " & vbCrLf & _
                "S for Thin(Skinny), or" & vbCrLf & _
                "M for Medium.", "Choose your Line Weight")
    If StrPtr(Style) = 0 Then Exit Sub   'User Canceled
    Select Case UCase(Style)
        Case "T"
        Thickness = xlThick
        Case "S"
        Thickness = xlThin
        Case "M"
        Thickness = xlMedium
        Case Else
        Exit Sub
    End Select
    Select Case UCase(Area)
        Case "A"
        Selection.BorderAround Weight:=Thickness
        Case "C"
        With Selection
        .Borders(xlInsideVertical).LineStyle = xlContinuous
        .Borders(xlInsideVertical).Weight = Thickness
        .BorderAround Weight:=Thickness
        End With
        Case "R"
        With Selection
        .Borders(xlInsideHorizontal).LineStyle = xlContinuous
        .Borders(xlInsideHorizontal).Weight = Thickness
        .BorderAround Weight:=Thickness
        End With
        Case "U"
        With Selection
        .Borders(xlInsideHorizontal).LineStyle = xlContinuous
        .Borders(xlInsideHorizontal).Weight = Thickness
        End With
        Case Else
        Exit Sub
    End Select
End Sub