Thefts of catalytic converters have increased in the Billngs area in the last few years.
There are no identifying marks or numbers to show that they're stolen.
In the last couple of weeks, the Billings police started a new program to put some markings on those exhaust systems to alert recycling companies and also to maybe try to deter the thieves.
Sgt. Nate West described sound of a vehicle if a catalytic converter is stolen and missing.
"You start your vehicle like when you hear a backfire," he said. "It almost sounds like a gunshot, like one of those loud aftermarket exhaust pipes mufflers. You definitely know something's wrong."
West says they're stolen for the precious metals, including platinum, palladium and rhodium.
The police department's plan is to have auto shops in Billings stencil "Stolen Call 911 Billings PD" on the catalytic converter with bright colored paint.
"Somebody crawls under a vehicle with intent to take this they see that it might deter them," West said.
Catalytic converter thefts started increasing in 2020, with police receiving reports of 60 stolen in some months.
"2020 is when we really noticed. You're talking like five, six fold of these thefts happening," West said.
Police say thefts increased at the end of 2021 and with the winter weather have decreased at the start of 2022.
"A simple cut of the exhaust pipe on each side of the catalytic converter they get that piece they want and they're off to the next one," said West.
Now about 50 auto shops have agreed to help with the stenciling.
"The Billiings Police Department has asked us to assist in this," said Jared McDermott, L.P. Anderson Point S Tire general manager. "We're happy to help any way that we can."
McDermott says it's much easier to have help from an auto shop rather than putting on your own paint.
"We're already under the vehicle and we can do this very quickly," McDermott said. "You do have to use a very special paint for the catalytic converters because they get very hot. So we have a high temperature exhaust paint that actually bakes on and therefore it's very difficult to remove later."
"If we can have an impact, I think we're willing to go as far as we can to to curb the problem," said West.
More information is available on the Billings Police Crime Prevention Center Facebook page.
West also suggested calling the center at (406) 247-8590.
