VINTAGE EXPANDING WESTWOOD FUEL PETROL CAP POSSIBLY BSA OR NORTON WD

I believe to be for a war dept. BSA or possibly Norton. It's a large expanding cap & is stamped "Westwood". It still works fine. It's quite large. The rolled hinge is 13.5mm. With the expanding wings in the open position approx 78mm & when closed approx 68mm.

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