The M113 entered Army service in 1961, featuring light aluminum armor that could protect its crew against small arms fire and shrapnel. In April 1962 the South Vietnamese, right, began receiving M113s, which the shocked Viet Cong dubbed “Green Dragons.” However, the VC quickly learned the M113’s vulnerabilities to mines, rocket propelled grenades and recoilless rifles. Even so, the versatile M113 was used throughout the war. About 85,000 were built and served in more than 50 armies. (History/Granger, NYC)