Distinctive Unit Insignia. Description: A Gold metal and enamel device 1 1/8 inches (2.86 cm) in height overall consisting of a shield blazoned: Gules a fess wavy Argent; on a canton Or an anchor debruised by two oars in saltire of the field. Attached below the shield is a Gold scroll inscribed "VOLENS ET POTENS" in Red letters.
         Symbolism: Scarlet and white are the colors of the Corps of Engineers. The wavy fess alludes to the outstanding feat accomplished by the organization in World War I, in which the regiment bridged the Vesle under heavy fire, making possible the forcing of the passage by the Division. The yellow canton, representative of the color of the Engineers' facing when the old companies of the regiment were organized in 1861, refers to the 2d Engineers, from which the 4th Engineers was organized in 1916. The device on the canton was the badge of the Engineers and Pontoniers of the Civil War.
         Background: The distinctive unit insignia was originally approved for the 4th Regiment Engineers on 18 February 1927. It was redesignated for the 4th Engineer Battalion on 5 December 1940.

Coat of Arms.
         Blazon:
                 Shield: Gules, a fess wavy Argent, on a canton Or an anchor debruised by two oars in saltire of the field.
                 Crest: From a wreath Argent and Gules a dexter cubit arm mailed Proper grasping four arrows Gules armed and feathered Argent.
                 Motto: VOLENS ET POTENS (Willing and Able).
         Symbolism:
                 Shield: Scarlet and white are the colors of the Corps of Engineers. The wavy fess alludes to the outstanding feat accomplished by the organization in World War I, in which the regiment bridged the Vesle under heavy fire, making possible the forcing of the passage by the Division. The yellow canton, representative of the color of the Engineers' facing when the old companies of the regiment were organized in 1861, refers to the 2d Engineers, from which the 4th Engineers was organized in 1916. The device on the canton was the badge of the Engineers and Pontoniers of the Civil War.
                 Crest: The mailed hand and arrows are indicative of the combat capabilities of the unit, the number of arrows corresponding to the numerical designation of the battalion.
         Background: The coat of arms was originally approved for the 4th Engineers on 21 January 1921. It was redesignated for the 4th Engineer Battalion on 4 December 1940.