Sub Find_Matches()
Dim CompareRange As Variant, x As Variant, y As Variant
Set CompareRange = Worksheets("REQ").Range("A1:A600")
For Each x In Selection
For Each y In CompareRange
If x = y Then Range(Cells(x.Row, "A"), Cells(x.Row, "E")).Interior.ColorIndex = 6
Next y
Next x
End Sub