170510-N-DH124-763 FORT HUNTER LIGGETT, Calif. (May 10, 2017) Construction Mechanics 2nd Class Jeremy Colbert and Adam Hager, both assigned to Naval Mobile Construction Battalion (NMCB) 4, use the M256A1 chemical agent detector kit after a simulated chemical, biological and radiological attack at Fort Hunter Liggett, Calif., during the battalions’ field training exercise. The exercise prepares and tests the battalion’s ability to enter hostile locations, build assigned construction projects and defend against enemy attacks using realistic scenarios while being evaluated by Naval Construction Group 1. (U.S. Navy photo by Mass Communication Specialist 1st Class Rosalie Chang/Released)