With keyless entry on the rise amongst modern cars it has become more important than ever to protect your car key whilst it’s not in use. You heard me right – the car key, not the car! Left unprotected, thieves are using RF signal extenders to detect, copy and swipe your luxury ride with minimal disturbance.
“Keyless entry may save you a few minutes during the morning rush, but keyless car theft is no joke. Car key signal blockers are a cheap and simple way to keep your car safe, so you can enjoy a good night’s sleep”
With 109,000 cars stolen across the United Kingdom in the past year, it’s wise to take the necessary precautions to keep your car safe. In this article we review a range of car key signal blockers on the market, and look at how exactly they stand up to the transmitters and range extenders used by criminals to gain unwarranted access to your vehicle whilst it’s parked out front.
The Car Key Signal Blockers we Reviewed
The vast majority of the RFID car key signal blocking cases we tested were in the form of a pouch or wallet that were also suitable for a phone or debit/credit card for multipurpose use. A wallet tends to be cheaper, slimmer and all around more practical, however we did also test a high end box case designed specifically for car keys if that’s what you’re in the market for. The prices varied from around £6 at the budget end to the £35 custom made key cases for the more premium products. All products featured are suitable and were successful and blocking the signal emitted from modern car keys, however some did prove better than others. For more detail see the full reviews below for each product.
|Product||Image||Dimensions (cm)||Pouch / Case||Award||Price|
|Defender Signal Blocker||18.5 x 11.5||Pouch||Best Budget|
|Sentry Signal Blocker||13 x 9.5||Pouch|
|Vonetti Alpha Shield||8.6 x 4.8||Case|
|Monojoy Tweed Pouch||15 x 9||Pouch||Our Recommendation|
|Wisdompro Shielding Wallet||19 x 8.9||Pouch|
|Minder Signal Blocker||20 x 12||Pouch||Most Customisation|
1. Defender Signal Blocker – Best Budget Option
The Defender is our budget option, offering a plain black(or white) but smart pouch with the necessary RPF material to block the signal from your car key. You can pick up slightly cheaper options, but the extra £1 is a worthwhile spend, offering a slightly higher build quality with seams that won’t fray after a few uses.
The inner case is lined with a specially manufactured RPF material that blocks any incoming or outgoing RFID signals. Whilst in the wallet it protects your car key from amplifying signal devices that make your keyless systems vulnerable to attack from thieves.
The pouch measures 18.5 x 11.5 x 1cm. This means you can also use the pouch for mobile phones, debit/credit cards and passports if you wish. It’s also large enough to house a few sets of keys, so you can keep any spares safe in the home as an added bonus.
We did a few tests with the Defender. With the key in the pouch, the buttons pressed through the material had no impact. As soon as you remove them, the buttons jump back into life and the car unlocks. We tried the same with a mobile phone for incoming calls. Whilst in the pouch, no calls can be received. Everything worked as advertised.
- Price – low cost solution
- Multi purpose
- Durable material
- Available in black or white
- Two pockets inside – only one(larger) is lined with blocking material
2. Sentry Signal Car Key Blocker – With Keychain
This car key RFID blocker from Sentry Signal is designed to be practical. Unlike some of the other products we tested the pouch is designed for the specific purpose of holding a car key, with a velcro seal that holds the key tight inside.
The pouch also comes with a key chain, looped around the top of the pouch, designed to attach to your key. It’s practical and means you won’t forget the pouch when you leave the house, however when the keys inside, you have to have the chain looping out a small gap at the top. You also need the car key out of the pouch when in the car – so although practical for some, others including myself, might prefer to remove it altogether.
When we tested the Sentry Signal car signal blocker by placing the key in the pouch and pressing the buttons it worked without fault from a distance, but at very close (next to) proximity the buttons were still able to unlock the car. For all intensive purposes the product is fit for purpose, and the best budget option we could find on the market that worked whilst being “just for keys”.
The pouch is 13 x 9.5 cm, so will fit a bank card if required, and a spare key if kept in the home. As with other products on the market there are two pockets inside the pouch, with the back one providing the signal blocking effects. If you have a few keychains then they will also fit into the pouch, however it’s won’t be a “neat and tidy” fit.
- Low cost
- Smaller pouch, 13 x 9.5 cm
- Good build quality
- Two pockets, only one signal blocking
- Less effective when stood next to the car
3. Vonetti Alpha Shield Premium – High End Case
The Alpha Shield Premium is the only box we reviewed that was fit for purpose. It’s a high quality product manufactured in Germany by a company called Alpha Shield. The box measures 8.6 x 4.8 x 2.7 cm, and fits one key only. The aluminium case will block any signals from being amplified from your car key or keyfob whilst inside.
The box has a slide lid on top for easy access, with a padded suede interior to keep your key safe from rattling around or scratching. The outside is smooth to the touch and feels good in the hand. It’s sturdy and won’t break if dropped on the floor.
We tested this product in the same fashion as the others, with strong results. Whilst the key is inside the car won’t open or start. Ease of access is not an issue for practicality; just slide the lid and remove they key. Since performing these tests, my spares, and the wife’s, sit in a pouch, but this has become my main signal blocker for day to day use as I carry the key alone without anything else attached. I highly recommended this if you’re in the market for a top end product.
- Box design that works
- Specifically for car keys
- Blocks all signal – including car start
- High price – but you get what you pay for
- For car key only, no good with a keychain
4. Monojoy Key Signal Blocker – Our Worth It Winner
The Monojoy keyless car signal blocker is the mid range product we tested, and the highest priced pouch. For the extra money you get yourself a quality product with a far more stylish appearance to the others we have reviewed. It’s not breaking the bank at just a few pounds above the bland pouches, and I must admit, would be my preference if going for a pouch.
After testing my wife has continued to use the Monojoy pouch. She likes the design, and it fits her keyring with house keys, albeit a little snug. There is a handy key chain hoop on the back for added practicality and the dimensions come in at 15 x 9 cm. Like the other pouches there are two pockets inside, with only one providing the signal blocking protection.
We tested the pouch in the same fashion to the others, at distance, next to and in the car for start/stop. It passed all three, on both our cars. No issues to report with the design or function of the signal blocking protection.
- Stylish design
- High quality tweed material
- Can fit keys with a keyring
- No cons, mid priced but quality product
5. Wisdompro Shielding Pouch – multi purpose
The Wisdompro is best described as a wallet as opposed to pouch, and is the only product reviewed where the opening flap is on the longer edge. The material resembles that of the typical user manual cover/folder you find in the glove box of your car. It comes in two colours, black or pink, and I opted to purchase the black version.
The wallet is the largest product reviewed at 19 x 8.9cm and suitable for a number of products, not just your car keys. This allows it to double up as a handy signal blocker on holidays, especially city breaks on public transport, for your cards and phone as well. Inside the wallet there are two sections, with the larger lined in the RFID signal blocking material. If you have additional bits and bobs on your keyring alongside the key that you’d rather not remove, then this is the number one choice for you. I put all 4 car keys we were testing with in the wallet without an issue.
The wallet works well, passing all tests at all distances. The RFID signal protection blocked car key and keyfob signal as well as any incoming calls to my phone. Only plus side is that the Wisdompro was also able to comfortably fit my iphone 8 with the chunky case I have on it. Another small bonus.
- Large design for multiple uses
- Reasonably priced
- Not practical for out and about use
6. Minder Signal Blocker – multi coloured options
The final product to be tested and reviewed is the Minder signal blocker. This is the only product available in an array of colours allowing you to customise it to something a little less bland than the other products. If you are going to use something every day, it may as well be in a colour you enjoy looking at. It also comes in at the bottom end of the price spectrum offering good value for money.
The Minder comes in at 20 x 12 cm, so slightly bigger than some of the other pouches. If you do want something to use daily for the car keys on the go, as opposed to just in the house, then you may want to consider something slightly smaller. The build quality is good with seams that look like they will last. Only problem I did have were marks showing up after using it for a week on the green colour I selected, however they did wipe off easily with a damp sponge.
The signal blocking worked as advertised for the car keys. At distance and close up the keys has no effect on opening the car. So if that’s what you’re in the market for then not a problem. IT did however have some hit and miss results with my iphone. Sometimes it blocked the calls, other times the call would still go through, so as a primary for a phone as well – I would suggest the Monojoy.
- Large enough for more than 1 key
- Full selection of colour options
- Much larger than it looks
Frequently Asked Questions
How does keyless entry theft work?
Criminals often use two relay boxes to gain unwarranted access to a vehicle. One will stand next to your front door or wall to pick up the signal being omitted from your car key. The other will stand next to the car to trick it into thinking the key is right there, next to the door. Once the car unlocks, and the engine is started you can drive away. In some cases thieves will use this signal alongside more complex gear to make a copy of your key – to remove any warning after driving away that the key is no longer in the vehicle.
Is my car at risk of keyless entry theft?
If you have keyless entry as a car feature, then yes. These features are not only reserved for luxury vehicles, with the technology widely available from Ford Kugas, to Honda CRVs.
Do you have an example of a car being stolen with keyless entry?
See the video below released by the West Midlands Policy of a Mercedes C Class Coupe being stolen by two thieves with a relay device