Sgt. Donald Christensen, an explosive ordnance disposal technician with Company C, Battalion Landing Team 1st Battalion, 4th Marines, 31st Marine Expeditionary Unit, moves into position as helicopters prepare to land during Marine Expeditionary Unit Exercise at Okinawa, Japan, on Jan. 12, 2012. This training is a multi-week training exercise conducted prior to every 31st Marine Expeditionary Unit deployment.