Review on MONOJOY Faraday Box for Key Fob, Key Fob Protector, Signal 🔒 Blocker - Car Key Fob & Cell Phone RF Blocker, RFID Book Box by Chris Burks

Works very well. Unless I insert an optional locking section, the only way I can use the car's keyless fob feature is to bring the entire book/box within a meter of the car. Also, the signal weakens so much that the car doesn't see it (that's good). If I put an extra blocking element in there, even just a foot away from the car door, the signal will be so weak that the door won't open, which is VERY good. So I won't use the extra part that much, but if I get paranoid I will (maybe at night).