Antique German KPM Style Porcelain Plaque (Wagner, Bisson)

Hand painted, signed "Wagner" on the lower right. Marked on the back with incised porcelain mark. Unfortunately, I cannot identify the mark - the incised shield with the crown can be attributed to a few porcelain factories.

The plaque is framed in the beautiful brass frame. Excellent condition consistent with age and use. Please, look at the pictures as they are part of the description. Oval Plaque - 5 1/8" x 4". Frame - 6 15/16" x 5 13/16". There is NO RETURN for items unless I have made a fundamental mistake in my item description. The reason of the return should be based on facts that I have not referred to.