This is a museum quality reproduction of a WWI Air Service Officer Collar Badge featuring the aviation section of the US Signal Corp that was authorized in April 1918 and therefore very short lived. This reproduction is made in darkened bronze with the wings and globe in sterling silver. They are held together by tabs as were the originals. A picture of this collar can be found in Duncan Campbels books on page 37. You are purchasing a matched set of two insignia.