Marines, with the 22nd Marine Expeditionary Unit, examine and evaluate individual water filters during an Experimental Forward Operating Base aboard Marine Corps Base Camp Lejeune, N.C., May 4, 2012. Marines and sailors participating provided input on individual energy and water purification equipment. The Expeditionary Energy Office, Headquarters, Marine Corps, coordinated the XFOB for input from the servicemembers and suggestions for improvement. - Marines, with the 22nd Marine Expeditionary Unit, examine and evaluate individual water filters during an Experimental Forward Operating Base aboard Marine Corps Base Camp Lejeune, N.C., May 4, 2012. Marines and sailors participating provided input on individual energy and water purification equipment. The Expeditionary Energy Office, Headquarters, Marine Corps, coordinated the XFOB for input from the servicemembers and suggestions for improvement.