RAF operations room tote board height plaque '44'

RAF Plaques, Indicators, Height.  Air Ministry reference 54A/1073.  Incredibly rare operations room display panel / tote board plaque used in RAF filter and sector operations rooms during the Battle of Britain and beyond to display important information relating to the height of an enemy raid.  This small blue painted metal plaque or 'tag' is screen printed in white with the number '44', measures approximately 1.25" x 1" (33 x 23mm) and would have been positioned on a display panel or tote board along with other plaques representing the raid serial number, strength, speed and so on.  This is the same pattern as some black on white plaques found at West Malling about 20 years ago but the first 'height' pattern we've ever come across.  We were fortunate to find a small quantity, most of which have gone straight into our collection, this is one of a few duplicates to be offered for sale.  A fantastic opportunity to create a small Operations room display.  Excellent condition.  Stock code M29283.