Adafruit RFID / NFC Smart Ring - Size 11 - NTAG213

What did Lord Sauron, when forging the One Ring in the fires of Mount Doom, forget to include? An embedded RFID/NFC transponder! The RFID/NFC Smart Ring is impervious to dragon fire, designed to communicate silently with your smartphone, tablet, or computer for boundless connectivity.Equipped with two MiFare Ultralight C - NTAG 213's, each offering 144 bytes of read/write memory, one is discreetly placed on the inside of the ring and the other beneath the jewel. Unlock limitless possibilities: launch apps, unlock your phone, transmit URLs, or even control an Arduino with a swift gesture.Featuring an inner diameter of 21mm, the RFID/NFC Smart Ring comes in a variety of sizes to accommodate all hands. NFC technology enables effortless data exchange as if mirroring a very short range Bluetooth without the need for authentication. This ring seamlessly integrates with any NFC/RFID reader supporting ISO 14443-3A MiFare Ultralight/NTAG, making it an indispensable tool for RFID-tag projects.