philippe::niquille | regular niche market thoughts

I always wondered how does beeping RFID shoplifting protections work, so I disassembled one.

The setup is quite simple. A needle is stuck in the cone with four small metal balls. They hold the needle down and make it impossible to remove the needle from clothes in the shop. At the counter they then place the thing upside down on a strong magnet and allow the needle to escape the cone, voilà. The simple winding allows the device to be detected when someone exits the shop without removing it.