Lance Cpl. Alex Rowan, a combat engineer with 4th Combat Engineer Battalion, 4th Marine Division, stationed out of Bessemer, Alabama, runs to take cover before the Anti-Personnel Obstacle Breaching System detonates during the SAPPER Leaders Course at Marine Corps Base Camp Lejeune, North Carolina, June 26, 2015. During the course, the Marines used assault and breaching techniques to clear a wire obstacle using line charges that utilized C4 explosives and their APOBS. - Lance Cpl. Alex Rowan, a combat engineer with 4th Combat Engineer Battalion, 4th Marine Division, stationed out of Bessemer, Alabama, runs to take cover before the Anti-Personnel Obstacle Breaching System detonates during the SAPPER Leaders Course at Marine Corps Base Camp Lejeune, North Carolina, June 26, 2015. During the course, the Marines used assault and breaching techniques to clear a wire obstacle using line charges that utilized C4 explosives and their APOBS.