The Marine Corps was paying $60,000 more than it was supposed to for a type of radio cable since 2007, according to Stars and Stripes.

The cable was discovered to be overpriced in October 2016, when Marine Cpl. Riki Clement had to fix a radio. After being told that the needed parts would take six to eight months to arrive, he decided to reverse engineer a replacement using old parts and found out its true cost was actually closer to $4,000.

Later that month, the Marine Corps said the corporal had saved the government $15 million.

The defense contractor that makes the cable, Astronics, had been charging $64,000 for each cable. Astronics did not immediately respond to request for comment.

“There may be a good reason for the price, but based on us taking apart the cable and researching the individual parts, we’ve found no reason for this part to cost as much as it does,” Clement told Stars and Stripes in December.