Illustration by Lille Allen / The Verge

See if this sounds familiar: You are in a weird part of town and get cash from a sketchy ATM. The next day, you pay for gas at a pump-side terminal that doesn’t look quite right.

A few days after that, you get a call from your bank saying someone’s using your card in a nightclub across town. It’s not a disaster, but you have to spend some time going through your recent charges, and you also have to wait a few days for the replacement card to come, all while you’re wondering which ATM was the one that skimmed your card number.

Against such a common problem, what are your options? For the particularly paranoid, enter the Hunter Cat.

What is it?

The Hunter Cat is a small device powered by a coin battery and roughly the size and dimensions of (you guessed it) a credit card. It’s pretty simple! You swipe it into the vape shop or gas station ATM in question, check for one of three lights, and if you get a “warning” or “dangerous” light, then consider another location. When you want to try again, just click the reset button. The card even has a sleep function that shuts the device off after 15 seconds to save on battery life.

The Hunter Cat is produced by Electronic Cats and Salvador Mendoza and powered by a tiny ATMEL SAMD11 Arm Microcontroller. It works by detecting the number of magnetic heads in a given card reader. If everything’s kosher, you’ll only see one magnetic head – the head the ATM uses to read your card. If the Hunter Cat sees multiple devices, it will give you a warning light to let you know something’s off. Most likely, someone has added a second card reader on top of the ATM to steal your credit card information.

What can it do?

The Hunter Cat can ferret out malicious card skimmers hidden inside ATMs and save you the time and hassle of calling your bank. It should, however, be noted that at this time, the Hunter Cat cannot protect your NFC card data from being stolen, although they have also released a product called the Hunter Cat NFC. While NFC skimming is a risk, tap cards tend to have better security features than the magnetic stripe of the card, and so it’s more of a hassle than just getting you at a gas station that way or stealing your info online.

In addition to regular magnetic stripe skimmers, there are devices known as card “shimmers.” Unlike card skimmers, card shimmers work by getting in between the reader and the EMV chip of your card. That said, magnetic strips are currently the oldest and most viable way to steal your credit card info, and it doesn’t just happen at the gas station pump.

How much of a threat is it?

Many of the tools we have been talking about are specifically designed to hack, but this one is meant to save you from getting hacked. To the average consumer, it could be a potential godsend. To a scammer trying to skim your card via the magnetic stripe? Well, they won’t get your card info and order a bunch of iTunes gift cards or whatever. Sucks to be them! They are just gonna have to settle on one of the countless other viable paths to steal your credit card information.

Could I use it myself?

Absolutely — it couldn’t be easier. If you travel a lot or are paranoid about getting skimmed, you probably would get some use out of this device. The Hunter Cat is not terribly expensive or even intrusive, so it can be easily stored in your car’s glove compartment or your bag on the go, although it is larger than a credit card by design, so it may not fit in your wallet. The lights are also easy to use and read, making it excellent for non-hackers out there. Just don’t expect it to protect you from anything more sophisticated than a simple magnetic stripe reader, and remember that in many places, magnetic stripes are explicitly being phased out for EMV, tap cards, and other contactless payment systems.