Senior Airman Nicholas Appenzeller, 8th Maintenance Squadron aerospace ground equipment journeyman, looks into the control panel of a heater to check the status of the liquids inside at Kunsan Air Base, Republic of Korea, Nov. 10, 2015. The heater is used during the winter time to provide heat for crew chiefs who work outside in extreme cold temperatures. (U.S. Air Force photo by Staff Sgt. Nick Wilson/Released)