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Flying this weekend? This $6 USB condom will protect your data from suspicious outlets

A selection of PortaPow USB condoms, also known as data blockers

Adrian Kingsley-Hughes/ZDNET

There are three things that I make sure I do when I’m out and about. I seek out the best coffee I can find. I make sure I use a VPN when using public Wi-Fi, and I always make sure I use a USB data blocker, otherwise known as a USB condom<!–>, whenever I use a third-party charger (such as those you find in coffee shops).

OK, first off, what on Earth is a USB condom? 

Also: How to use public Wi-Fi safely: 5 tips you need to know before you connect

A USB condom is a small dongle that adds a layer of protection between your device and the charging point you’re attaching it to. 

Remember, USB isn’t just a charging protocol, it also allows data to flow back and forth, and while most of the time this data flow is safe, it is possible to create a malicious charging port that can do bad things, such as plant malware on your device or steal your data.

So, back to the USB condom data blockers.

Sold by PortaPow<!–>, these are a super-simple, cheap solution to the problem of using untrusted USB charging devices. Simply plug it into a port, and any and all potential data transfer between the charger and your device is severed, putting an air gap between the USB port and your smartphone, laptop, or whatever you are charging.

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There are data blockers for USB-A-to-USB-A<!–>, USB-A-to-USB-C–>, and USB-C-to-USB-C<!–>.

For the super-paranoid, there are also transparent data blockers–>, the idea being that you can tell if they’ve been tampered with in any way.

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Adrian Kingsley-Hughes/ZDNET

The job of the USB condom is simple — to turn any USB port into a charge-only port by blocking all the data lines. Sure, you could make one yourself from a USB cable (slice it up and cut the data cables), but with these bespoke data blockers costing only about $7, it really doesn’t seem worth the hassle.

Another company that makes high-quality charge-only data-blocking cables is StarTech. These cables are one meter long and come inUSB-A-to-microUSB<!–>, USB-A-to-USB-C–>, and USB-A-to-USB-A<!–>. These are priced around $12, all have a cutout on the USB-A port to show no data lines, and all are marked “power only.’

Also: My favorite USB-C accessory of all time scores a magnetic upgrade

Bear in mind: While a data blocker can prevent data transfer, the port might still be able to damage a device, either through accident, misconfiguration, or malicious tampering. For example, devices such as those from USB Kill–> can be used to, well, kill devices that are connected to them by sending high voltage through the USB port, frying the delicate electronics.

Nasty!

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Adrian Kingsley-Hughes/ZDNET