Iron Brigade and was previously called the "Black Hat" Brigade. The 3rd Brigade Combat Team, 1st Infantry Division was known as the Iron Brigade from its formation in 1917 through World War I, World War II and Vietnam, until some time in the early 2000s when, for reasons that are still unclear, the name was changed to Duke Brigade. The unit crest was an Iron Cross in a triangle, it appears that that was also changed. The 3rd Brigade of the 4th Infantry Division is also known as the Iron Brigade. Its unit crest is similar to the medals issued to veterans
Battle of the Iron Triangle in Bến Cát on the afternoon of the 16th and on the 17th began reinforcing the RF holding the bridge and moving against the PAVN's blocking positions west of the bridgehead. The weakness of the ARVN bridgehead and the strength of the enemy positions in An Dien, which included antitank guns and tanks, made it impractical to send any armor of the 318th across the An Dien bridge at this time. Meanwhile, the 322nd Task Force moved from Tây Ninh Province to Phú Cường and was ordered to prepare to attack into the Triangle along Route 14 in order to