As the heaviest Armor Brigade, consisting of the 6th Battalion, 6th Infantry; the 1st Battalion, 35th Armor; the 2nd Battalion, 70th Armor; the 4th Battalion, 70th Armor; the 2nd Battalion, 1st Field Artillery and the 47th Support Battalion (Forward), the 2nd Brigade, 1st Armored Division acted as the lead brigade during combat operations. On 27 February, the 2nd Brigade was fully engaged with the Medina's 2nd Brigade and, in the largest single engagement of the war, destroyed 61 Iraqi T-72/T-55 tanks, 34 APCs and five SA-13 air defense systems in less than one hour.