160915-N-CN059-0205 KWAJALEIN, Marshall Islands (Sept. 15, 2016) Construction Mechanic 3rd Class Ryan Filo, left, and Construction Mechanic 3rd Class Andersen Gardner, assigned to Underwater Construction Team (UCT) 2, tests the density of the metal pylons of a pier in Kwajalein, Marshal Islands while participating in Valiant Shield Sep. 15, 2016. Valiant Shield is a biennial U.S. Air Force, Navy and Marine Corps exercise held in and around Guam, focusing on real-world proficiency in sustaining joint forces at sea, in the air, on land and in cyberspace. (U.S. Navy Combat Camera Photo by Mass Communication Specialist 2nd Class Daniel Rolston/Released)