Note:1.Please make sure your vehicle key fob is put in to inner layer since only the Inner layer blocks signals.2.Please do not wash the faraday bag; keep the interior dry,or it may lose signal-blocking function.Good radiation protection.3.Please allow 1-3cm error due to manual measurement.4.Due to different monitor and camera lights may cause slight color differences.What is a Faraday Key Fob ProtectorIt is a structure that blocks the passage of radio signals.Inner layer can be used to block cell phone or car key signal, and the black layer can be used to store your cash, cards, etc.Why you choose it for your carEvery 43 seconds a car is stolen in the US, which is close to a million vehicles per year. Thieves are now more sophisticated than ever, opening and operating your car without needing to break in. Using signal amplification to gain unauthorized access to your car, these thieves can steal your car with total ease.Specifications:Type: Faraday BagMaterial: Oxford clothItem Color: BlackAttention Intensity: 90DbFunction Efficiency: 99.9%Inner Size: 189cm\/7.13.5\