U.S. Marines with the 26th Marine Expeditionary Unit inflate their uniforms during a swim qualification course at the Area 5 pool aboard Marine Corps Base Camp Lejeune, N.C., March 17, 2015. Marines must tread water for 10 minutes during the qualification to demonstrate they can properly use their uniform as a flotation device for survival in water. (U.S. Marine Corps photo by Cpl. Joshua W. Brown/Released)