Early and Late 1939 Mercury Hubcaps. When the 1939 Mercury was first released in late 1938, it was actually labelled as a Ford Mercury. However, the powers to be at Ford thought that it should be a stand alone make.
Now that I have my glasses on, the Hubcap in question does have the same design as the revised 1939 Mercury Hubcap, but it appears that it is a small "dog dish" hubcap, whereas, the 1939 Mercury has a centre piece that attaches to a larger base to fit the "wide five" bolt pattern. So the question still remains - what is that mystery Mercury Hubcap?