Incredibly rare 'Raid Block' number used in RAF filter and sector operations rooms during the Battle of Britain and beyond to display important information relating to the strength of an enemy raid. The wooden or metal raid block itself was normally positioned at the head of the plotting path and provided information such as strength, height and whether the aircraft were 'hostile', 'friendly' or 'unknown'. This small white painted metal counter or 'tile' is screen printed with the number '18', measures approximately 3 x 2.5cm and would have been positioned on the raid block along with other tiles representing height, raid serial number and so on. Found at West Malling some years ago. A fantastic opportunity to create a small Operations room display. Some light scratching and wear but in good overall condition. Stock code M18248.