ShieldPer bend Argent and Sanguine, in chief on a Greek cross Gules a fleur-de-lis Or.
CrestThat for the regiments and separate battalions of the California Army National Guard: On a wreath of the colors Argent and Sanguine, the setting sun behind a grizzly bear passant on a grassy field, all Proper.
MottoSERVIANT ET SAVIANT (Serve and Save).
ShieldThe shield is maroon and white, the colors of the Medical Corps. The cross indicates the character of the organization while the gold fleur-de-lis represents service overseas.
CrestThe crest is that of the California Army National Guard.
The coat of arms was originally approved for the 115th Medical Regiment on 17 December 1941. It was redesignated for the 115th Medical Battalion on 20 July 1942. It was amended to change the nomenclature of the unit to read “115th Medical Battalion, California National Guard” as well as to change the history to include only California National Guard units on 26 August 1942. It was redesignated for the 40th Armored Medical Battalion on 9 February 1955. The insignia was redesignated for the 40th Medical Battalion on 13 April 1961. It was rescinded on 13 September 1976.