Corporal Albert Perez III, administrative specialist, 15th Marine Expeditionary Unit, tests the seal of his M50 Joint Service General Purpose Mask during his unit's chemical, biological, radiological and nuclear defense mask confidence training at Camp Margarita aboard Camp Pendleton, Calif., Sept. 17. Perez, 21, is a native of Los Angeles. (U.S. Marine Corps photo by Cpl. Emmanuel Ramos/Released)
<br>Unit: 15th Marine Expeditionary Unit
Cpl. Emmanuel Ramos
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