I picked up these two items today and I was wondering if I could get some info on both. The National is a Ohio company which was the main reason I picked it up but I have never heard of the company before. Does anyone have any background info on the company?

The other is a porcelain used car dealership sign that the guy I got it off said went in a Oldsmobile and Buick dealership. Does anyone know if this type of sign was used just strictly in Olds and Buick dealerships or was it used in other car manufacturers as well?

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