An Afghan National Army (ANA) soldier of the 203rd Corps applies a chest seal during a combat lifesavers course at Forward Operating Base Thunder, Paktia province, Afghanistan, April 21, 2014. The ANA soldiers have become proficient on the medical skills required to save lives of others while conducting operations in a hostile area. (U.S. Army photo by Pfc. Dixie Rae Liwanag/Released)