GIs & Duster On Route Nine

View of US Army soldiers and their M42 Duster (a 40 mm, self-propelled anti-aircraft gun) stopped along Route Nine, I Corps (South Vietnam), Republic of Vietnam, February 20, 1971. One lies under the vehicle, one with binoculars sits on the gun barrels, another rests his chin on his knee, and the fourth listens on a field radio, where he learns of the ambush of another armored cavalry troop further along the road. (Photo by Christopher Jensen/Getty Images)

An Army officer in northern South Vietnam converses on a field radio perched on an M42 Duster, an anti-aircraft vehicle, in 1971. (Christopher Jensen/Getty Images)

Christopher Jensen/Getty Images