A combat engineer of 4-3 Brigade Special Troops Battalion, 4th Infantry Brigade Combat Team, 3rd Infantry Division, throws a grappling hook to ensure and area is free of booby traps before breaching a concertina wire obstacle in a combined arms live-fire exercise on Fort Stewart, Ga., Jan. 28, 2015. (U.S. Army Photo by Sgt. Joshua Laidacker, 4th IBCT, 3rd ID, Public Affairs)