U.S. Air Force Airman 1st Class Elfie Diltz, a 35th Maintenance Squadron aircraft metals technology technician, scrubs away slag from a steel bar at Misawa Air Base, Japan, Feb. 1, 2017. Slag consist of all the impurities left over from heated metal. The substance remains on the surface which is brushed away with a wired brush after a weld. (U.S. Air Force photo by Airman 1st Class Sadie Colbert)