A "square" shield with ogee base 2 1/4 inches (5.72 cm) in length by 2 inches (5.08 cm) in width; Or (Yellow) two flaunches Gules (Red).
The colors are old Spanish colors, the yellow narrowed by the red indicating the Isthmus.
The shoulder sleeve insignia was approved on 16 August 1922. It was cancelled on 2 February 1948.