An uncirculated example of the Pennsylvania National Guard Mexican Border Service medal of 1916/17, in original manufacturer's box and complete with ribbon bar. Impossible to upgrade from.
 
This medal recognizes those military service members who were assigned to the U.S.-Mexico border at the period of time when the United States was on the verge of all-out war with Mexico. While US Army forces had moved past the border and into Mexico, the mission of the national guard units was to protect towns and ranches on the US side of the border from any attacks.