Cap never had a sewn insignia & there’s oxidation under insignia prong indicating it’s been on cap. Clearly navy style field cap. Insignia is nicely detailed 2 dimensional brass. I had seen a period photo of Japanese factory/arsenal workers sitting behind tables wearing caps with same insignia. I think aviation related. Photo was posted on one of the FB groups. If anyone has seen photo or can provide a link to it I’d greatly appreciate it! My cap has had a leather oval added as a backing. No markings or stamps anywhere.

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