Coolus helmet type G is believed to have been used during the third quarter of the I century AD. The original helmet was found in excavations in Drusenheim, near Haguenau in Alsace. Scholars believe that the original helmet was worn by a soldier belonging to the 4th Legion of Macedonia. The original helmet was found in brass but there are variations of the same helmet in bronze as well. This type of helmet was used by the Roman army and therefore was constructed in large numbers. The modern-day replicas of this helmet are mainly found in steel and brass.