Car Key Signal Blocker Case --- Rough Internal size : 17 cm x 9.8 cm x 1.4 cm (we fit both our main car key and spare in one pouch). --- Many modern cars use keyless entry technology, allowing for remote access to the vehicle and its ignition. --- The Defender Signal Blocker is lined with specialist RPF material preventing your key fob from communicating with your vehicle. --- This product blocks radio signals as well as passive RFID including calls, SMS, Wi-Fi, Bluetooth, RFID, 4G and NFC. --- Defender Signal Blocker - Mobile phone blocking signal jamming pouch with RPF for road safety and RFID blocking car fob protection. Color: Black. Why do you need the Faraday Bag? Most keyless fobs carry identification chips that pick up radio signals sent out by their car. The vehicle recognizes the fob when it's in range and unlocks the doors.
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