A Silver color metal and enamel device 1 1/8 inches (2.86 cm) in height overall consisting of a shield blazoned: Gules, five chevronels enhanced and interlaced Argent. Attached below the shield a Silver scroll inscribed "TIAKOTEMEN" in Black letters.
The red shield and white charges are the colors of the Corps of Engineers, and indicates the unit's origin. The chevronels represent the allocation of the unit to Utah, Nevada, Wyoming, Montana and Idaho. The Indian motto, translated "Fight On", is derived from the Selish.
The distinctive unit insignia was originally approved for the 329th Regiment Engineers, Organized Reserves on 5 December 1925. It was redesignated for the 329th Engineer Battalion on 1 October 1942. The insignia was rescinded on 7 May 1976. As an exception to policy, the distinctive unit insignia is reinstated and redesignated effective this date for the 3d Brigade, 104th Division.