Insignia Description
A gold color metal and enamel device 1 1/16inches (2.70 cm) in height overall consisting of an open black isosceles triangle with point up and a gold vine leaf within it, surmounted below the apex and extending beyond laterally, a horizontal white diamond bearing a Korean taeguk, and issuing from base, inclined with the triangle and below the diamond, two red lightning flashes, all below a blue scroll of three arcs terminating at the lower sides of the flashes and inscribed "HONOR VIGILANCE DUTY" in gold letters.

Symbolism
The diamond and taeguk simulate an eye and the lighting flashes connote technology; together they represent the vigilance, celerity and communication of Army Security. They also allude to the lineage and service of the organization, World War II and Korea. The vine leaf refers to the Rhine Province and denotes the unit's participation in the Rhineland Campaign. The taeguk represents Korea where the unit participated in six campaigns. It is also used to symbolize the award of the Meritorious Unit Commendation Streamer inscribed "KOREA." Black is used on the triangle to connote iron and refers to the Republic of Korea Presidential Unit Citation Streamer awarded the organization with the inscription "THE IRON TRIANGLE."

History
The distinctive unit insignia was originally approved for the 304th Army Security Agency Battalion on 29 April 1976. It was redesignated for the 304th Military Intelligence Battalion on 2 May 1990.

Source: The US Army Institute of Heraldry