I have no idea of what different versions of visor there may be. Obviously there is the Internal Security visor, with the rubber flange, which according to the protective sleeve with mine is made by Helmets Ltd in Hertfordshire. And then there's the de-mining visor which from what I observe has no rubber flange but must have a thicker and stronger facemask altogether. What else? There can't be many other options, surely. Information, please!