Best signal-blocking Faraday bags for car keys in 2022
Reduce the risk of your car being stolen with a specially lined Faraday wallet
As technology makes our lives easier and manufacturers find smarter ways to integrate the latest innovations into cars, new risks are created that criminals look to take advantage of. Years ago if a thief wanted to steal your car with the key, they would go to elaborate measures, including fishing through your letterbox hoping you had left your car keys by the door. Now it's a high tech game of cat and mouse as the thieves have moved on to stealthy solutions, including electronic boxes to relay signals from smart keys that allow owners to enter their car without pressing a button. The answer to this new risk is a Faraday bag.
If your car has a smart key that allows you to enter and start the engine without handling it then thieves can potentially target the frequency unless it is blocked. Once they have detected a signal they can trick the car into opening and drive off without damaging the vehicle or triggering the alarm. This method is gaining popularity amongst thieves of cars that are stolen to order, or with criminals that want to use the vehicle for other crimes and therefore keen to avoid any obvious damage that may make the car stand out.
A Faraday bag eliminates this concern. Lined with a layer of metal, it essentially isolates your key and its frequency so that it isn’t transmitted or copied. A Faraday bag also works with smartphones and credit cards.
A Faraday bag will beat the criminals at their own game, but which one is best? We put eight of them to the test to get the answer.
How the Faraday bags were tested
In our first test we tried the proximity sensor of our smart key by attempting to open the door on our test vehicle with the car’s keys in a Faraday bag held next to the driver’s door. After that, we pressed the button on the key while it remained in the Faraday bag to see if this caused a response from the vehicle. Finally, we sat behind the wheel and attempted to start the car with the key still in the Faraday bag.
We also assessed the build quality, cost and usability of the bags. An app was used to check the phone, Bluetooth and Wi-Fi signal-blocking capabilities.
The results were very close because all the products worked as the manufacturers stated. With this in mind, we turned to the quality, practicality and value for money offered by each of the products.. The best signal blocker was the Defender, a Faraday bag that’s big enough to accommodate other items too. Both the Disklabs KS1 and the Ecence weren’t far behind.
Defender Signal Blocker
Price: Around £5
Size (cm): 18.5 x 11.5
Our winner successfully blocked all signals and had excellent build quality. Surprisingly, it’s the cheapest to buy too. It’s the second largest bag out of the ones tested, easily handling larger phones, but it could be a bit excessive if you only have a small set of keys. We were happy to accept its size given the benefits the Defender gives you for the price.
Disklabs Key Shield Faraday Bag KS1
Price: Around £28
Size (cm): 12 x 10
The Disklabs bag instantly inspired confidence, as it was the only one here given the ‘Secured by Design’ accreditation from the police. The build quality was among the best here and the effectiveness of the signal blocking worked even with the flap still open. It would fit most keys nicely. It’s a pricey choice, but it feels like a sound investment.
Ecence RFID Radiation Protection Bag
Price: Around £9
Size (cm): 12.5 x 8
Designed for key use only, the Ecence bag is exactly the same as the Halfords and B-G, aside from the fact it’s cheaper, hence why we rated this one higher. It performed signal blocking well, the material itself thick and reassuring. The only quibble we had was the lack of stitching quality, especially at the bottom of the bag and whether this had the potential to wear with use.
B-G RFID Keyless Entry Car Key Fob Signal Blocking Faraday Bag MIS1003
Price: Around £3
Size (cm): 12.5 x 8
A great feature of the B-G is that you can choose two sizes; a smaller one for just keys or a larger one for items like phones. The build and results were almost identical to the Ecence bag, just for slightly more money. The B-G had a chrome ring on the back, perhaps for hanging the bag on your key hook indoors. There was also a keyring on the top.
Halfords Anti RFID Theft Wallet
Size (cm): 12.5 x 8
The Halfords bag lost out to its cousin the Ecence on price. As with the Ecence and B-G though, build and signal blocking were up to standard, aside from perhaps the stitching in the bottom of the bag. Different to its relations, the Halfords bag specifically mentions it can be used with credit cards. You could easily fit a few in there too.
TVL Anti Scan Wallet
Price: Around £24
Size (cm): 14 x 9.5
TVL is the second most expensive here, but as with the Disklabs KS1 and PS1 bag, you could see the quality would mean it would last even with daily use. The lining worked well for blocking the key signal and also worked with phones when the flap was closed. The vinyl coating adds to the sturdy feel, but doesn’t bode well for folding it away into a pocket.
Disklabs Phone Shield Faraday Bag PS1
Price: Around £31
Size (cm): 11.5 x 19
The most expensive but also the biggest, measuring up larger than the Defender. The PS1 also has the same police recognition as its smaller sibling, the KS1. It could fit phones and keys together inside, with only a slight struggle when including larger key sets. Despite the price, the size makes it worth the extra cost, although it would be a bit too cumbersome for easy storage in a pocket or bag.
TrackingUK Faraday Key Signal Blocking Wallet
Price: Around £12
Size (cm): 14.3 x 10
For subtlety, the TrackingUK bag was the best. It was by far the lightest of the set and easy to fold away and store. Blocking phone signals was a little more hit and miss but it worked perfectly well on the keys. The price for the quality of material and stitching seemed a bit high though, particularly given it didn’t seem as durable as some other options here.
Looking for other ways to protect your car from keyless go theft? Read our guide on the best steering locks to stop thieves in their tracks.
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