On a shield, oblong in shape and arched at both ends, 3 inches (7.62 cm) in height and 2 inches (5.08 cm) in width overall, within a 1/8 inch (.32 cm) white border, a vertical white arrow between 2 inwardly curved white arrows. The upper area between the curved arrows is red and the balance is blue.
The sweeping prongs simulate the elements of the unit in attack and in resembling a trident also allude to amphibious assault.
The shoulder sleeve insignia was approved on 28 July 1966. (TIOH Dwg. No. A-1-402)