Incredibly rare Operations Room / Filter Room hand plotting 'counter' used to display important information relating to an enemy raid. When details of aircraft were received at Group Filter Room level, the information was interpreted on a map table using plotting 'counters' in the form of coloured arrows, discs and shields. Arrows indicated the direction of aircraft seen over land by Observers or over sea by radiolocation. Shields indicated aircraft heard over land or sea by Observers and discs indicated circling aircraft. The colour of the plotting pieces related directly to those on the Sector clock such that information was updated every 5 minutes. Arrows in seven different colours were used in the Filter room. Here we are offering a single 'blue' coloured arrow, approximately 1.5"/3.5cm long, made from pressed fibre. There is soiling/wear but overall condition is good. A fantastic opportunity to create a small Battle of Britain Operations/Filter Room display. NB, map shown for display purposes only. Stock code M25676.