The Distinguished Floor Buffing Cross.
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Heh. That's because it's a Navy medal. Back in the day at Service Schools Command at Great Lakes, if you screwed up on something that wasn't major the Chief would assign you to "Extra Military Instruction" (EMI) which consisted of reporting in at 5 PM and buffing floors for an hour. I earned my medal at Electrician's Mate "A" school, when I graduated in 1975 I held the record for number of hours of EMI worked off.