Shield
Per chevron enhanced Azure (Light Blue) and Gules, on a chevron embattled counter-embattled Or a stylized turret Sable charged with a cross pomm of the field, in base and above a fountain a sword point down and key with ward to base saltirewise of the third.
Crest
That for the regiments and separate battalions of the Puerto Rico Army National Guard: From a wreath Or and Azure (Light Blue), upon a closed book Gules with pages edged Or a paschal lamb couchant with staff and banner of San Juan (Gules a cross Argent) all Proper.
Motto
SERVICE WATER PRIDE.
Shield
Light blue is one of the colors traditionally used by Quartermaster Corps, the original unit designation, and gold is emblematic of honor and achievement. Red embodies courage and zeal. The embattled chevron symbolizes strength and support and highlights fortification and defense. The round sentry box alludes to "The Devil's Sentry" at San Cristobal, San Juan, and gives emphasis to the location and heritage of the Battalion. The gold sword and key are adapted from the Quartermaster insignia. The heraldic water symbol and the motto reflect the organization's former water supply mission and the commitment to proudly serve and support its customers.
Crest
The crest is that of the Puerto Rico Army National Guard.
The coat of arms was originally approved for the 162d Quartermaster Battalion on 20 Jul 2001. It was redesignated effective 1 September 2008, for the 3678th Support Battalion with the symbolism updated.