Just put car key into the faraday case and close to your car, if the car door won't open, it proves that it totally blocks signals. SECURE YOUR CAR COMPACT & NOT BULKY EASY TO DISTINGUISH HIGH-QUALITY PU LEATHER STURDY HOOK DOUBLE MILITARY-GRADE FARADY FABRICS The inside of faraday bags are made of high-quality double-layer shielding fabric, therefore, when your car key is placed in our rfid blocking pouch, it completely blocks the connection with the key fob to prevent anyone from picking up your vehicle signal and stealing your car. Ditch the other bulky faraday cage and use our compact shielding bag for peace of mind at all times After our rigorous testing, this car key blocker case can hold all regular size car keys.
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