U.S. Marines with the 1st Tank Battalion detachment, Battalion Landing Team 2nd Battalion, 1st Marines, 11th Marine Expeditionary Unit (MEU), work to replace an M1A1 Abrams tank engine during sustainment training at D’Arta Plage, Djibouti, Nov. 6. The 11th MEU is deployed as a theater reserve and crisis response force throughout U.S. Central Command and the U.S. 5th Fleet area of responsibility. (U.S. Marine Corps photos by Gunnery Sgt. Rome M. Lazarus/Released)