Blocking the Signal Adopt RFID blocking material, which can prevent thieves from amplifying the signal of your car key and protect property safety. Get your car protected to shield against break-ins and keyless ignition theft. RFID Protection The smaller/front pocket is anti-radiation, best for storing ID cards, bank cards, etc. The larger/back pocket is for signal blocking, best for storing car key fobs. It can block all the signals of phone, WI-FI, Bluetooth, 5G, NFC, RFID and other devices put into it. Sturdy and Durable Diyife faraday pouch is constructed with premium carbon fiber textured material and two-layers of shielding materials. It provides signal blocking functions as well as a luxurious fashionable appearance. Easy to Carry Dimensions: 3.5" x 5.7". Secure close flap with elastic accommodates multiple sizes of keychains and small devices. The integrated keychain hole provides more flexibility. Enclose your keys on the key chain, use the external hook to hang the bag on your jeans or backpack.