Sergeant David Losacano, a radio operator with Combat Logistics Battalion 24, 24th Marine Expeditionary Unit, does a “brass check” to ensure a round is inserted into his M4 carbine during a live-fire exercise aboard the amphibious dock landing ship USS Fort McHenry (LSD 43), Jan. 24, 2015. The 24th MEU is embarked on the ships of the Iwo Jima Amphibious Ready Group and deployed to maintain regional security in the U.S. 5th Fleet area of operations. (U.S. Marine Corps photo by Sgt. Devin Nichols)