Kriegsmarine U boat badge WWI maker marked

Very rare WWI German U boat badge maker marked Walter Schott fec,

The U-boat War Badge was instituted during the First World War on February 1, 1918. It was awarded to recognize U-boat crews who had completed three war patrols. The badge was worn on the lower left side of the uniform and was oval shaped resembling a wreath of laurel leaves. A submarine lay across the center and the German State Crown (Reichskrone) was inlaid at the top center of the wreath.