Final answer:
The Good Conduct Medal uses service stars or clasp loops to denote subsequent awards, with bronze and silver variations indicating the number of additional awards.
Step-by-step explanation:
To denote second and subsequent awards of the Good Conduct Medal, the United States military uses devices known as service stars or clasp loops (also known as knots). These are attached to the ribbon of the medal. For instance, in the Army and Air Force, a small bronze star is used for each subsequent award, with a silver star indicating five bronze service stars. The Navy, Marine Corps, and Coast Guard use bronze and silver clasps, with the form of a loop, also signifying additional awards. This practice is common across many military award systems to signify multiple awards of the same medal without the need to issue separate medals for each instance.