The Hertz Corp. is being sued in federal court in Newark by U.S. customers who say they were hit with undisclosed currency conversion charges when renting vehicles abroad using credit cards.

The putative class action, Margulis v. The Hertz Corp., alleges that the 4-year-old practice violates New Jersey’s Consumer Fraud Act, which carries the potential of treble damages and attorney fee shifting if the plaintiffs prevail.