U.S. soldiers with 3rd Squadron, 71st Cavalry Regiment, 3rd Brigade, 10th Mountain Division set up a 120mm M120 mortar firing system while Air Force Staff Sgt. Zachary Lopez records them on Forward Operation Base Lightning, in Paktiya province, Afghanistan, Nov. 13, 2013. The M120 mortar firing system is being set up to provide base defense. (U.S. Army photo by Spc. Amber Stephens/Released)