The M-1965 Field Jacket, also known as the M65, is a popular field jacket designed for the US military. It was introduced into US military service in 1965 to replace the M-1951 field jacket, an evolution of a Second World War design, the M-1943 field jacket. The M-65 field jacket was widely used by United States troops during the Vietnam War in which the jacket became useful for troops serving in the Central Highlands of South Vietnam, as well as keeping a soldier warm from the cool weather conditions that came after monsoonal rains.