A Massachusetts man has pleaded guilty to shipping potentially dangerous counterfeit semiconductors to the U.S. Navy base in Connecticut for use in nuclear submarines.

Peter Picone, of Methuen, Massachusetts, took a plea deal Tuesday in federal court in Hartford. He faces up to 46 months in prison when he is sentenced Aug. 22.

Picone says he made a big mistake.

Authorities say Picone sold counterfeit parts to the Navy and military contractors that bore the trademarks of legitimate Massachusetts companies, such as National Semiconductor Inc. and Motorola Inc.

Prosecutors say the fraud cost its victims about $2.5 million. A grand jury indictment said Picone and others shipped the circuits to the base between November 2011 and February 2012.

Authorities said the counterfeit semiconductors also raised national security concerns.