A nice original WWI US War Service Shipbuilding badge here. Some discoloration from age is present on the front and back of this badge, but it is minor and does not detract from the badge's overall appearance. A working pin and catch remain on the reverse, along with the serial number 76473. 
 
The United States entered World War I in April 1917. Within days, the federal government created the Emergency Fleet Corporation (EFC) to construct a fleet of merchant ships. The EFC hired the American International Shipbuilding Corporation to build and operate the largest shipyard in the world: Hog Island, near Philadelphia. This badge identified the wearer as a member of the World War I Hog Island shipbuilding team.