The aim of a Faraday pouch is to contain the signal transmitted from a car’s key. To do this, the bag must be lined with something that doesn’t allow the signal to escape. This is usually metallic and frequently involves a number of layers to ensure the signal is well and truly contained. These things are sometimes called Faraday bags, pouches, even cages or RFID bags. But no matter what we call them, the aim is to contain the signal transmitted by a car’s key. This prevents car thieves from grabbing the signal and using it to steal your car. To see how good the item really is, put your mobile phone in it (assuming it fits). Then ring your phone. A fully functioning Faraday bag should prevent the signal getting through to your phone. What makes a good Faraday pouch? Obviously it has to fulfil its primary purpose of isolating the signal from the key. Good ones are made from several layers of copper and plastic. But if you want to make your own, you could use aluminium kitchen foil and paper. A poor-quality Faraday bag may stop working because it has failed and can no longer prevent the signal from escaping.

Streetwize Car Key Signal Blocking Pouch Black, Double Pack

Just as they don’t allow the signal to escape, neither do these bags allow any signal to enter. So once in a Faraday bag, your car key will neither transmit nor receive. Do Faraday bags work for car keys? In some cases, biscuit tins will work as a Faraday bag; in other cases not. Put your keys in a biscuit tin and if it has a tight-fitting lid, it should prevent signal getting through. If the signals are very strong, it might not. It’s the same with a fridge. In some cases, the seal on a fridge door will be sufficient to keep the signal from the key in and any external signals out. In other cases, it won’t isolate the key sufficiently to be any use. Some people might want one to put their mobile phone in; some might want them for their car keys. It’s worth remembering that car keys can differ dramatically in size nowadays too. Do you need a Faraday box for car keys?Bauer Consumer Media Ltd, Company number 01176085; Bauer Radio Limited, Company number: 1394141; Registered office: Media House, Peterborough Business Park, Lynch Wood, Peterborough PE2 6EA and H Bauer Publishing, Company number: LP003328; Registered office: The Lantern, 75 Hampstead Road, London NW1 2PL This kind of crime is referred to as ‘keyless theft’ or ‘relay theft’ because of the way the signal is relayed. The whole process can take a team who know what they’re doing less than a minute. How do Faraday pouches work?

Car Key Signal Blocker Pouch with Hook Securing Keyring Car Key Signal Blocker Pouch with Hook Securing Keyring

Relay theft has been around for a couple of years now and car makers have got wise to crooks. Some car companies now make keys that don’t emit a signal unless they’re moving, or after they’ve been stationary for a short period of time. Other’s make keys that can be turned off if they’re not needed. Put your key in the sandwich bag then wrap that in aluminium foil, carefully sealing three edges. Make sure you can still access the sandwich bag’s opening (the fourth edge that you don’t seal).Whenever you think your car key might be vulnerable to having its signal grabbed. Ironically, the easiest cars to steal using relay theft are those parked on people’s drives. The thief knows exactly where the keys for that car are: somewhere behind the front door. The bag must be fit for purpose too. Some people might want a Faraday bag that’s portable; some might want one that they can just leave in their house for when they’re at home. The latter might be able to get away with a less robust article.