Senior Airman Travis Mollema, 28th Communications Squadron client system technician, loosens a screw to replace a faulty heat sink unit in a computer during repairs at Ellsworth Air Force Base, S.D., Oct. 16, 2012. Heat sink units cool devices by dissipating surrounding heat to prevent electronic systems from overheating and failing. (U.S. Air Force photo by Airman 1st Class Zachary Hada/Released)