A very nice example of an area title for Chislehurst & Sidcup. A number of these Civil Defence area markings feature the blue backing with old gold lettering with a merrow edging (similar ones for Greenwich and other areas are known to exist). I'm not entirely sure of the method used to manufacture these, but it looks like the lettering was woven into the backing fabric (if you now the method used let me know).
This particular example sold for £70 plus shipping on eBay.
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