Dim xTbl As Table
   Dim sVar1 As WdLineWidth           'For the Last Row: Value to put as Top Border
   Dim sVar2 As WdLineWidth           'For the Last Row: Value to put as Bottom Border
   Dim LineWidth As Borders
    
    sVar1 = InputBox("Last Row - Enter the size value from the below choices before the symbole = for the Top Border." _
      & vbCr & "Exemple : 2 =0.25/ 4 =0.50/ 6 =0.75/ 8 =1.00/" _
      & vbCr & "12 =1.50/ 18 =2.25/ 24 =3.00/ 36 =4.50/ 48 =6.00.", "SUGGESTION", "8")

    sVar2 = InputBox("Last Row - Enter the size value from the below choices before the symbole = for the Bottom Border." _
      & vbCr & "Exemple : 2 =0.25/ 4 =0.50/ 6 =0.75/ 8 =1.00/" _
      & vbCr & "12 =1.50/ 18 =2.25/ 24 =3.00/ 36 =4.50/ 48 =6.00.", "SUGGESTION", "18")
    
    For Each xTbl In ActiveDocument.Tables
      xTbl.Rows.Last.Range.Select

     With Selection.Range
       With .Borders(wdBorderTop)
            .LineStyle = wdLineStyleSingle
            .LineWidth = sVar1
            .Color = wdColorAutomatic
       End With

       With .Borders(wdBorderBottom)
            .LineStyle = wdLineStyleSingle
            .LineWidth = sVar2
            .Color = wdColorAutomatic
       End With
     End With
  
   Next xTbl
  
  On Error GoTo 0