RAPPEL REFLEX U.S. Marine Corps 1st Lt. Sean Williams rappels down a 30-meter rock face while participating in the Republic of Korea Marine Corps Basic Rangers Course in Pohang, Korea, July 6, 2010. Williams, an amphibious assault vehilce platoon commander, is assigned to the 3rd Marine Division. More than 50 U.S. Marines participated in the course. SHARE: Download: Full Size (0.09 MB) Credit: VIRIN: 661935-G-KIZ45-438.jpg Photo Gallery