Signal Blocking Function: The inner layer of the Faraday pouch is made of special shielded material, provides a complete signal blocker for your vehicle key. No longer worry about thieves amplifying your key signal and opening your car, effectively preventing remote access to your remotes. 2 PACK: We provide two pouches so you can protect a spare key in your house. One is carbon fiber, and the other is leather, both have signal blocking function to provide protection for your spare key. Perfect Size: Our Faraday Pouch measures 127mm x 80mm, except to ensure the Faraday bag works well, this handy keychain Faraday pouch is the perfect size to protect your keys, embedded access cards or other small electronic devices such as < p>Easy to Carry: Hook on the top to hang it on a backpack or jeans, or slip it into your purse and bag. This smooth leather signal blocker keychain is easy to carry and offers sophisticated style. Portable Fabric: This bag is made of premium RF shielding material