Following a spike in reported thefts, police in Montreal, Canada, are inviting motorists to register their vehicle’s catalytic converter to help deter criminals.

Drivers were invited to drive to one of three registration sites yesterday in the Montreal area, according to a report in the Montreal Gazette. Once there, the police gave owners an identification sticker and engraved an ID number into their catalytic converter with a related QR code.

One of the big problems with catalytic converter thefts for the police is that it’s very difficult to tell which unit came from which vehicle. With the ID numbers, police can at least track crimes and potentially return the converter to its rightful owner.

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Thefts of the devices have skyrocketed around Canada and the U.S. because of their value and the relative ease with which they can be stolen. Tall vehicles, like SUVs and pickup trucks, are at particular risk of having their catalytic converter stolen because thieves can crawl under them easily. Once under, little more than a hacksaw is needed to remove the converter.

The devices can then be sold for scrap. Catalytic converters use several precious metals, including platinum, palladium, and rhodium to scrub excess emissions out of a vehicle’s exhaust gasses. These metals’ values are often higher than gold and have been particularly high lately.

“Catalytic converters have been stolen for years,” the national director of investigative services at the Insurance Bureau of Canada told CBC News in March. “The difference lately is the price of precious metals, and obviously it’s the precious metals inside those catalytic converters that they’re looking to steal and then sell on the black market.”

Montreal police say that more registration operations may take place over the coming months. They also report that they have carried out several arrests in Quebec and Atlantic Canada in an effort to slow the crimes.