These are ZS 2 Richtungsanzeiger . Could be translated as junction or route indicator . They either show generic letters like F for Fernbahn mainline or S for SBahn commuter or show the direction you are going . For example B could be for Berlin , T for Teltow . If you tell us where you did take that picture we could maybe tell you exactly . <| sep |> In fairness , if he can ' t be seen then we can assume he moves at or near light speed , which means he should be able to more or less vaporize someone by tapping them on the shoulder . What percentage of that force would you need to merely kill something ? <| sep |> Apparently you ' ve already blown me away . You ' ve read my mind and given me the exact responses that would be most interesting . I ' d give you gold if I had money .