U.S. Air Force Staff Sgt. Curtis Harper, middle ground, assigned to the 455th Expeditionary Security Forces Squadron, performs an exercise designed to test his physical fitness and mental toughness during the Task Force Maverick Spur Ride inside the clamshell at Bagram Airfield, Afghanistan, Feb. 21, 2012. Participants comprised of Soldiers, Airmen, Sailors and civilians completed a road march and were tested on their proficiency in various tasks such as land navigation, evaluating a casualty, donning chemical protective masks and assembling weapons systems in order to earn their golden combat spurs, which indicates an experienced Service member who has deployed and experienced combat with an Army cavalry unit.