Frank Keys Jr. faces up to 40 years in prison after he was found cruising down the highway with more than 200 grams of heroin in the diaper he was wearing, federal officials said.

Keys, 38, of New Orleans was charged Friday by a federal grand jury. He got in trouble June 3 in St. John the Baptist Parish, north of New Orleans, when sheriff’s deputies pulled over the car he was in for a traffic violation, according to court documents.

The deputies and Drug Enforcement Agency special agents got permission to search the car, and a drug sniffing dog alerted them to the car’s passenger side.

The occupants were ordered out of the car, and patted down. During the pat-down, “officers felt a large hard object in the pants area on Keys,” according to a news release from the U.S. Attorney’s office.

Keys told officers he was wearing a diaper and when they asked if there was anything in the diaper, he “shook his head affirmatively.”

Officers then removed a package containing about 257 grams of heroin from the diaper.