Airman 1st Class Brandon Parks, 7th Equipment Maintenance Squadron nondestructive inspection journeyman, pours oil over a bolt at Dyess Air Force Base, Texas, Sept. 10, 2018. The oil has magnetic fibers which get stuck in any cracks that may be in the tool. Once the fibers are in the crack, they attract toward each other and result in the crack closing shut. (U.S. Air Force photo by Airman 1st Class Kylee Thomas)