Shield
Gules, a sentry-box of El Morro Castle, Puerto Rico, issuant from sinister base Or, in dexter chief a Man-O-War bird volant in bend baseward Proper, fimbriated and pierced by a spear of the second, in base six mullets, one, two and three of the last.
Crest
That for the regiments and separate battalions of the Puerto Rico Army National Guard: From a wreath Gules and Argent, 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
DENDEREMOS NUESTROS CIELOS (We Will Defend Our Skies).
Shield
The service of the former organization, the 123d Antiaircraft Artillery Gun Battalion, is indicated by the Man-O-War bird which represents a possible enemy. The spear depicts the elimination of an aircraft from the skies. The sentry box represents the constant defense of the skies and stars are indicative of the battalion number.
Crest
The crest is that of the Puerto Rico Army National Guard.
The coat of arms was originally approved for the 123d Coast Artillery Battalion on 18 Aug 1942. It was redesignated for the 123d Antiaircraft Artillery Gun Battalion on 3 Aug 1951. On 31 Jul 1961 the coat of arms was rescinded (cancelled). The coat of arms was approved in 30 Oct 1997, with blazon and symbolism revised, for the 201st Regiment.