In World War II, in the North African campaign, the commander of the 20th Engineer Regiment became increasingly frustrated by the huge numbers of diverse units and confusing task organizations. It was there that Colonel Caffrey directed the use of the Wavy Arrow to mark the 20th Engineer Regiment's vehicles and equipment. The red wavy arrow has been used ever since to mark 20th Engineer equipment, to include during combat operations in Vietnam and Iraq, and at present-day Fort Hood.
To this day, the newsletter of the 20th Combat Engineer Association of World War II uses the name "The Wavy Arrow."
In Vietnam, the "head shed" of Company A includes the Wavy Arrow on its sign. The newsletter of the 20th Engineer Battalion in Vietnam was named "The Wavy Arrow."
In Iraq, in the battalion's first deployment to Iraq as part of Operation Iraqi Freedom, the battalion headquarters displays the Wavy Arrow on both the building and its tactical operations tracked vehicle.
In Iraq, seen through a night vision device, a truck displays the wavy arrow.
In Iraq, in the battalion's second deployment to Operation Iraqi Freedom in 2006, the battalion commander and command sergeant major pose by a sign featuring the wavy arrow.
In 2005, the 20th Engineer Battalion was relieved from assignment to the 1st Cavalry Division and disbanded. The battalion headquarters remained in place, and was redesignated the 1st Special Troops Battalion, 1st Brigade, 1st Cavalry Division--a brand new type of unit. When the Army's Institute of Heraldry designed a unit crest for the new organization, they included the wavy red arrow as one of the major heraldic elements to show linkage to the history of the 20th Engineers.