U.S. Marine Corps Cpl. Leo Yoon, a Rockville, Md., native and a transmissions systems operator with 1st Battalion, 2d Marine Regiment, 2d Marine Division (MARDIV), operates an AN/PRC-160(V) radio as part of the 2d MARDIV High-Frequency (HF) Competition on Naval Submarine Base Kings Bay, Ga., July 12, 2021. The competition enhanced HF transmission proficiency and capabilities to prepare Marines for future expeditionary conflicts where the area is either contested or degraded. (U.S. Marine Corps photo by Lance Cpl. Brian Bolin Jr.) - U.S. Marine Corps Cpl. Leo Yoon, a Rockville, Md., native and a transmissions systems operator with 1st Battalion, 2d Marine Regiment, 2d Marine Division (MARDIV), operates an AN/PRC-160(V) radio as part of the 2d MARDIV High-Frequency (HF) Competition on Naval Submarine Base Kings Bay, Ga., July 12, 2021.