HOUSTON (KIAH) — According to insurance claim data obtained by AAA Texas, Harris County leads the state in the number of catalytic converter thefts.

That’s why, for a limited time, that group has partnered with several repair shops across the Houston-area to provide free protection from that crime.

Mechanics at shops like the West Galleria location of Christian Brothers Automotive mark catalytic converters with spray paint and then etch onto them the last four digits of the car’s vehicle identification number.

The paint can serve as a deterrent to thieves, and if they steal a marked catalytic converter anyway, the etching will help police prosecute them.

“That’s the problem, right, is you can’t prove that that (catalytic converter) is stolen,” AAA Texas Approved Auto Repair Manager Dave Skaien said. “So if you both had your (catalytic converters) stolen and neither of them are marked, how do we know those (catalytic converters) belong to your vehicle? So etching helps that.”

Thieves steal and then sell catalytic converters because of the valuable metals like platinum, palladium, and rhodium inside of them that can earn them hundreds of dollars apiece.

“Two of those metals are substantially more valuable than gold by the ounce,” Skaien said. “I can’t remember which one of the three, but (Monday) the price of one of those was $26,000 an ounce. So the metals are precious, they’re expensive, and people want them.”

AAA Texas says replacing a catalytic converter can cost between $1,500 and $7,500 depending on the type of car.

Driving a car without a catalytic converter is illegal.