1. Military Specification MIL-C-43199 Amendment 1 (21 January 1965)
The Army of the Republic of Vietnam Special Forces (the patch with the tiger and an open parachute) : (Vietnamese: Lực Lượng Đặc Biệt Quân Lực Việt Nam Cộng Hòa or LLDB) were the elite military units of the Army of the Republic of Vietnam (ARVN). Following the establishment of the Republic of Vietnam (commonly known as South Vietnam) in October 1955, the Special Forces were formed at Nha Trang in February 1956. During the rule of Ngô Đình Diệm, the Special Forces were run by his brother, Ngô Đình Nhu, until both were assassinated in November 1963 in a coup. The Special Forces were disbanded in 1975 when South Vietnam ceased to exist after the Fall of Saigon.
The South Vietnamese Regional Forces originally the Civil Guard (the patch with a crossed sword and cannon over a suit of armour on a yellow background) were a component of Army of the Republic of Vietnam (ARVN) territorial forces. Recruited locally they served as full-time province-level defence forces. In 1964, the Regional Forces were integrated into the ARVN and placed under the command of the Joint General Staff
MACV (patch on a shoulder) : U.S. Military Assistance Command, Vietnam was a joint-service command of the United States Department of Defense. MACV was created on 8 February 1962, in response to the increase in United States military assistance to South Vietnam. MACV was first implemented to assist the Military Assistance Advisory Group (MAAG) Vietnam, controlling every advisory and assistance effort in Vietnam, but was reorganized on 15 May 1964 and absorbed MAAG Vietnam to its command when combat unit deployment became too large for advisory group control. MACV was disestablished on 29 March 1973 and replaced by the Defense Attaché Office, Saigon (DAO).