Review on Faraday Box: Protect Your RFID Signals with Style! by Eric Pruett

Can't say these boxes work. I was so skeptical about the price but once I received and tested it I believed it 100%. If you have cars with automatic unlocking when you approach your car or software unlocking keys on your door handles to unlock your cars without taking the key out of your pocket/wallet. These boxes prevent this even if the box is placed next to the doorknob. If you can't even open the door with the keys in the drawer next to the doorknob, thieves definitely can't amplify the signal to unlock your car in the middle of the night. Now I sleep better at night knowing that thieves won't get into my car unless they smash the window or learn some other mechanical secret/skill to get into the car.