The 3678th Combat Sustainment Support Battalion Distinctive Unit Insignia (DUI), also called a unit crest or referred to as a DUI for short, was originally approved on 20 July 2001. It was redesignated for the 3678th Support Battalion, with revised symbolism, and given an effective date of 1 September 2008.
The insignia features two components: a black scroll (the color of solidarity and support) with the unit motto of “Service Water Pride” inscribed in gold letters (the color of excellence and achievement), and a shieldlike badge charged with imagery related to its function and missions. In the upper portion of the shield is a light blue area, one of the colors traditionally used in Quartermaster heraldry; the gold found throughout the shields is, like the script, indicative of excellence and honor. A scarlet area stands for zeal and courage, and an embattled gold chevron denotes strength, support, and suggests defense and fortification.
A black sentry box is an allusion to the “Devil’s Sentry” at San Cristobal, emphasizing the heritage and location of the Battalion on the island of Puerto Rico. A crossed sword and key are adapted from the branch insignia of the Quartermaster Corps, while the roundel with wavy lines is an heraldic symbol for water; this recalls the organization’s former mission of water supply that is also referenced in its motto.
Also known as a unit crest or DUI, a Distinctive Unit Insignia is worn by all Soldiers (except General Officers) in units that have been authorized to be issued the device. It is worn centered on the shoulder loops of the Army Green Service Uniform (AGSU) and the blue Army Service Uniform (ASU, Enlisted only) with the base of the insignia toward the outside shoulder seam. Current regulations do not permit the DUI to be worn on the Dress variations of either uniform, however.
More guidance on wear of the DUI is found in DA Pamphlet 670-1, Section 21-22, "Distinctive unit insignia" and 21–3(d) and (e), "Beret" and "Garrison Cap," respectively.
♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦
As a unit in the Puerto Rico Army National Guard, the 3678th Combat Sustainment Support Battalion has a mandate to carry out both Federal and State missions as needed.
In 2018, for example, the Battalion was called into Federal service and deployed to Afghanistan to provide support for Operation Enduring Freedom, while in later January 2020 the Puerto Rican government turned to the Battalion for assistance in distributing water and food and erecting emergency shelters following two earthquakes measuring 5.8 and 6.4 on the Richter scale that had taken place on the 6th and 7th of the month.
The 3678th Combat Sustainment Support Battalion is assigned to the 191st Regional Support Group, Puerto Rico Army National Guard.