The Army medical department can trace its history back to 1775 and the Siege of Boston. But it was not until 27 January 1882 that a Caduceus was used to designate the Medical Corp in a hat badge. It then vanished from use until 17 July 1902 when the Caduceus in gold was authorized for wear as a collar insignia. The size of the collars has changed over the year and by WWII they were 1 inch in size as made in this reproduction. This is a museum quality reproduction of the sterling insignia for an officer with a gold plate. Sold in a set of two as would be needed for a uniform.