I was on Greenline duty most of the time the 1st Air Cavalry was in Chu Lai, Vietnam. The ever present M16 rifle is in the background. The M60 machine gun is chambered and ready to fire. My bunker-mate and I also had grenades and a M79 grenade launcher. The green-line The line (perimeter) is the outer limit of our bunker. The area beyond the bunker belongs to the enemy. During the night we watched for any unusual movement. 1st Air Cavalry Division (Airmobile)