170915-N-YJ33-012 SANTA RITA, Guam (Sept. 15, 2017) Chief Equipment Operator Roy Summerville, assigned to Naval Mobile Construction Battalion 133, receives his combination cover from a mentor during a chief petty officer pinning ceremony held at the Naval Base Guam Theater, Sept. 15. The ceremony marks the culmination of a year-long training process known as CPO-365, which prepares first class petty officers to answer the call to be "the chief." (U.S. Navy photo Mass Communication Specialist 2nd Class Richard Miller/RELEASED)