U.S. Marines with Marine Wing Support Squadron 471, Marine Aircraft Group 41, 4th Marine Aircraft Wing, clean their M16A4 service rifles at Canadian Forces Base Cold Lake, Canada, June 19, 2019, in support of Sentinel Edge 19. Training exercises, such as SE19, ensure Reserve Marines are proficient and capable of successful integration with active-duty Marines, making MARFORRES critical to the Marine Corps’ Total Force. (U.S. Marine Corps photo by Lance Cpl. Jose Gonzalez)