Marines with 2nd Low Altitude Air Defense Battalion, 31st Marine Expeditionary Unit (MEU), fire a FIM-92 stinger missile from a Mark VI patrol boat during a live fire exercise in the Philippine Sea, Feb. 27, 2021. - Marines with 2nd Low Altitude Air Defense Battalion, 31st Marine Expeditionary Unit (MEU), fire a FIM-92 stinger missile from a Mark VI patrol boat during a live fire exercise in the Philippine Sea, Feb. 27, 2021.