U.S Air Force Tech. Sgt. Joseph Teresi, NCO in charge of Military Working Dogs assigned to 97th Security Forces Squadron, guides his dog to search concrete blocks, Mar. 29, 2019, at Altus Air Force Base, Okla. Highly sensitive peroxide-based explosives are now routinely being used by terrorists, so canine training with these chemicals provides readiness in these situations. (U.S. Air Force photo by Airman First Class Dallin Wrye)