A Gold color metal and enamel device 1 3/16 inches (3.02 cm) in height overall blazoned as follows: SHIELD: Or, on a bend Teal Blue between a double ward key in chief, wards downward, Sable and a lightning bolt Tenn in base, a sword point upward, blade, hand guard and pommel of the first, the hilt of the third; a base embattled of the third and masoned of the first charged with an escutcheon, per pale Azure (Dark Blue) and Gules, a pile throughout of the first. CREST: On a wreath Or and Teal blue, a lion's head erased of the first, collared four fusils Gules. Attached below the device a Black scroll inscribed "INNASCOR BELLUM" in Gold.
The bend denotes protection. Teal blue is the color traditionally associated with branch unassigned units. Black signifies fortitude. The double ward key indicates the dual role of the Battalion - the safekeeping of Military Intelligence and the security of the Military Police Company. The orange lightning bolt symbolizes speed and the unit's communication capabilities. The sword represents combat readiness and the Infantry operations. The embattled wall illustrates the Engineer responsibilities of the Battalion. On the top of the shield is the New Jersey State crest. The motto translates to "Born In War."
The distinctive unit insignia was originally approved for the Special Troops Battalion, 50th Brigade, 42d Infantry Division on 1 May 2009. It was amended to correct the unit designation to Special Troops Battalion, 50th Infantry Brigade Combat Team on 1 October 2009. The insignia was redesignated effective 1 September 2015, for the 104th Engineer Battalion with the symbolism updated.