U.S. Air Force Senior Airman Chaley Dyer, left, grapples Senior Airman Machelle Hill, both patrolmen with the 628th Security Forces Squadron, during Personal Apprehension Restraint Techniques (PART) and Mechanical Advantage Control Hold (MACH) training at the combat arms building on Joint Base Charleston, S.C., June 5, 2012. The MACH and PART training is an annual requirement for the Airmen. (U.S. Air Force photo by Airman 1st Class George Goslin/Released)