Frequency Focus Marines practice loading radio frequencies onto a communication radio during Exercise Northern Strike at Camp Grayling, Mich., Aug. 5, 2018. Marine Corps photo by Cpl. Niles Lee SHARE: Download: Full Size (3.93 MB) Tags: Marines, technology, Northcom, Northern Command, training, Marine Corps Credit: Cpl. Niles Lee VIRIN: 180805-M-HG783-1012D.JPG Photo Gallery