Two Philippine marines demonstrate defensive tactics and techniques to U.S. Marines during a martial arts expertise exchange at Crow Valley, Philippines, on April 10, 2013. The exchange is part of exercise Balikatan 2013, an annual bilateral training exercise designed to enhance interoperability between both forces and strengthen military-to-military relations. The U.S. Marines are attached to 3rd Battalion, 6th Marine Regiment, 2nd Marine Division, II Marine Expeditionary Force.