My wife is a Mosser and I was looking into her history; found there IS a coat of arms for a Mosser name from Germany.

Bear in mind that coats of arms aren't really tied to family names, they were granted to an individual who usually had the right to pass them on to his heir, but rarely could others in the family use it. But if you enjoy the fact that a coat of arms was once associated with your family name, this appears to be the only one tied to "Mosser" (at least by that exact spelling, there are about a dozen different arms tied to "Moser"!).

This coat of arms appears in J.B. Rietstap's Armorial General of European arms as well as Siebmacher's Wappenbuch of German arms, both reference works from the 1800s. There is no detail on which branch of the family carried these arms other than that they were of "Germany" (which at the time meant a smaller region roughly equal to most of north-western Germany today).

Anyway the attached file is a color copy of the Mosser coat of arms which I am posting here in case anyone else is interested in the history.

Edit: I'm not an expert on blazon (the jargon of heraldry), but I believe the description would be: "Quarterly, in the first and fourth azure a lion rampant crowned or and in the first contourné, in the second and third gules three reeds proper on a bed argent."

Dave