ShieldPer saltire Sable and Azure on a saltire Argent a key and lightning flash saltirewise of the second.
CrestThat for the regiments and separate battalions of the Army Reserve: On a wreath of the colors Argent and Azure (Oriental Blue), the Lexington Minute Man Proper. The statue of the Minute Man, Captain John Parker (H.H. Kitson, sculptor), stands on the Common in Lexington, Massachusetts.
MottoFORTIOR EX VIGILIS (Stronger After Vigilance).
ShieldOriental blue is one of the colors for the Army Security Agency. The color black represents secrecy and constancy. The saltire alludes to the joint functions of intelligence and security. The blue key is for guardianship and the lightning flash for electronic communications.
CrestThe crest is that of the United States Army Reserve.
The coat of arms was originally approved for the 314th Army Security Agency Battalion on 20 August 1963. It was amended to correct the wording in the blazon on 8 November 1963. It was cancelled on 9 June 1975. The insignia was reinstated and redesignated for the 138th Military Intelligence Battalion on 21 July 1983.