This is an item that is becoming exceedingly rare. The reason being that when there were many around nobody bothered with them. "Quartermaster's Comment":- Michael and I had a very good look at this Flash. It is NOT per a 'D' Company within the Artillery or Engineers which is red and blue, but was adopted from that as used by Army Intelligence Units, which is what Recce and Special Forces is all about. Dudley Wall has illustrated it nicely per pages 50 and 51 of his book. See No. 11 on Page 50. I have not handled one of these before in the last two years!!!!