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Thieves are targeting catalytic converters in greater numbers than ever. You're going to want to read this—especially if you drive a Toyota Prius.

Thefts of catalytic converters continue to climb at an alarming rate, and the pandemic and its resulting economic issues have made their resale value rise even further. Aside from comprehensive insurance coverage and setting your alarm to its most sensitive setting, is there anything we vehicle owners can do to make sure we're not stuck with expensive repairs? Short answer: It depends.

Catalytic converters are generally easy to access; it takes an average of three minutes for a thief to slide under a car or (especially) a truck and simply cut it out with a hacksaw or Sawzall. It's a crime of convenience. Hybrid vehicles are particularly vulnerable, because those cats utilize even more of the precious metals within. Aside from typical anti-theft best practices like parking in well-lit areas and setting the car alarm to its most sensitive option, there's not a lot most of us can do to stop cat converter theft.

We can, however, make it a lot harder. Depending on the type of vehicle you own, there are several anti-theft devices on the market. Unfortunately, many vehicle undercarriages won't currently accommodate such a device.

If you're a Toyota Prius driver, you're in luck. A few aftermarket companies have developed metal shields that easily bolt to the undercarriage of 2004-up Priuses—and even some late-model Tacoma pickups. Check out the selection of cat shields and covers below, as well as a couple of other suggestions: a device designed to "lock" your catalytic converter in place and a motion-sensitive alarm to sense when the cat itself it being messed with.

Is one of these worth it for you? Most insurance policies don't cover cat theft—and because it's a model-specific, EPA-regulated emissions device, catalytic-converter replacement can cost thousands from your dealer. It's your call, but if we had a Prius, we'd definitely give a shield a shot.

Watching a Catalytic Converter in Action Is Absolutely Mesmerizing

Let's start with a product that's inexpensive and universal. It's "universal" because it hangs loosely via metal hose clamps to the exhaust under the car, so, theoretically, it should fit nearly any car or truck. Just set the motion-based alarm with a fob whenever the vehicle is parked, and it shrieks if it gets jostled or moved. To be fair, we could see a couple of potential drawbacks with this alarm—windy nights come to mind—but at this price, it's worth a shot if you don't own a Prius.

Okay, if this device works it might just be groundbreaking because it's compatible with most small gas and diesel engines of any brand. The CatClamp MAXX claims to form a nearly unbreakable barrier around your cat converter with a 5/16-inch-thick stainless steel cable that fits around 1 3/4- to 3-inch exhaust pipes. The heavy-duty wire acts like a cage around your converter, effectively tying it to your frame. We haven't tried it, but we're eager to hear from those who have.

Prius owners can relax a bit more than the rest of us (they seem pretty chill and unperturbed already anyway), because it's relatively easy to bolt a metal shield under their car. Of course, a determined thief will just remove the guard to get to the cat, but remember—catalytic converter thieves exist because cats are easy and fast to steal. Making yours harder than the next one dramatically reduces your chances of being a victim.

Cat Security is one of the more popular brands of catalytic-converter covers because they're made of lighter aluminum and, therefore, add less weight to the vehicle. These covers are easy to install too, with no welding required.

Also made of durable and corrosion-resistant aluminum, this shield is ideal for older Priuses with the 1.5L engine. Some users complain of rattling after installing heat shields such as this, but that's nothing some heat-resistant sealant such as Permatex can't fix.

As we said above, unless you're a Prius owner most cat shields won't work for your vehicle. However, if you drive a late-model Toyota Tacoma 4x4 with a 3.5L engine you're in luck because MillerCat has designed a cat shield just for you. And if they can do it for this truck, more models should be on the horizon.