Called balteus early in the empire and then cingulum militare in later times. The mark of a soldier, betls were not meant for civilian use. When worn over chainmail, the belt helped to take some of the weight off the soldier's shoulders. In the 1st century AD it was common to wear two belts in the army: one to hold the sword and one to hold the dagger (pugio). Foot soldiers wore their sword on the right, officers on their left. In the later Empire,this distinction fell away. The belts were rather narrow and decorated with metal plates all the way around. The decoration of each bronze plate could be quite ornate. They featured embossed or engraved designs, sometimes plated with tin, and in rare cases coated in silver foil. The engraving sometimes had blue-lack niello inlay.During the 1st and the 2nd centuries AD the belt supported several vertical strips of metal-studded leather, forming a groin guard. However judging by the meek protection offered a few dangling pieces of leather and the ornate decoration, it may be that this apron's more important purpose was to portray a man's social status as a soldier.
Gladiators had a different or a similar look of their balteus.