A small South Carolina parts supplier collected about $20.5 million over six years from the Pentagon for fraudulent shipping costs, including $998,798 for sending two 19-cent washers to a Texas base, U.S. officials said.

The company also billed and was paid $455,009 to ship three machine screws costing $1.31 each to Marines in Habbaniyah, Iraq, and $293,451 to ship an 89-cent split washer to Patrick Air Force Base in Cape Canaveral, Florida, Pentagon records show.

The owners of C&D Distributors in Lexington, South Carolina — twin sisters — exploited a flaw in an automated Defense Department purchasing system: bills for shipping to combat areas or U.S. bases that were labeled ``priority’‘ were usually paid automatically, said Cynthia Stroot, a Pentagon investigator.

C&D’s fraudulent billing started in 2000, Stroot, the Defense Criminal Investigative Service’s chief agent in Raleigh, North Carolina, said in an interview. ``As time went on they got more aggressive in the amounts they put in.’‘

The price the military paid for each item shipped rarely reached $100 and totaled just $68,000 over the six years in contrast to the $20.5 million paid for shipping, she said.