The converters are part of a vehicle's exhaust system and help remove pollutants.
They are full of rare metals including platinum, palladium, and rhodium.
Scrap-metal recyclers will pay anywhere from $50 to more than $350 for the converters.
And there isn't much car owners who don't have a garage can do to keep thieves away.
"It's just easy money," Mike Barefoot a mechanic at Martin's Auto Salvage in Raleigh told ABC11.
Barefoot once installed exhaust systems for a living and know that some catalytic converters are more valuable than others.
"Depending on the material, the amount of materials contained in each converter, it can make a big difference in what the value of the converter is," Barefoot said.
Some Raleigh car owners who are among the 64 victims of catalytic-converter thefts in the past year have been calling Martin's looking for replacement converters.
But used converters can only be sold for scrap.
Many of those calling are Honda owners.
The owner of Capital City Auto Brokers, who had catalytic converters stolen from six cars on two nights late last year, said the thieves often target Hondas.
"The converters have a higher concentration of platinum in them so they're more valuable to recyclers," said Alex Cardinell.
Cardinell said thefts from small businesses such as his hurt everyone.
"There has to be a better hustle," Cardinell said. "You know you're hurting the local economy when you are doing this to small businesses. And then we employ people locally. So it's going to have a trickle-down effect."
Unfortunately, if you don't have a garage it's hard to prevent the thefts.
Often the thieves work like a NASCAR pit crew with one person using a small jack to lift your car while the other crawls underneath with a reciprocating saw and with two cuts on the exhaust can walk away with a part worth hundreds of dollars in just seconds.
Locking your car and setting the alarm won't matter, Barefoot said.
"The converter's right there under the car. If it's locked up you can still get to it and get some quick easy money," he explained.
For those who don't have a garage, the Raleigh Police Department provides these tips:
- Park in well-lit areas
- Apartment complexes and businesses should get video surveillance for their parking lots
- Report any suspicious activity especially late at night if someone appears to be working under their car
- While not always practical, if you have the ability to store your vehicle in a garage or other secure location, do so
- When parking a vehicle overnight be aware of lighting, presence of cameras to monitor the area, if you have the ability restrict access to the vehicle particularly underneath
- If you are out walking your pet or have other reason to be up early call if you see or hear anything similar to machine operation or loud noises not typical for time of day
- Commercial locations should also consider the above with an overall evaluation of external security measures including cameras, fences, storage buildings locks etc.