171124-N-TY130-125 COMODORO RIVADAVIA, Argentina (Nov. 24, 2017) Lt. Damian Gutierrez, Argentine Navy Submarine Officer and Lt. Cdr. Commander Wendell Holmes, undersea rescue command engineer, discuss the modifications of the motor vessel Sophie Siem necessary for the Pressurized Rescue Module (PRM). Undersea Rescue Command, the U.S. Navy's only submarine rescue unit, mobilized to support the Argentine government's search and rescue efforts for the Argentine Navy diesel-electric submarine ARA San Juan. (U.S. Navy photo by Lt. Karl Schonberg/Released)