This RFID controller board uses the RC522 IC which operates at a frequency of 13.56MHz. This kit includes the RC522 RFID reader module and two S50 RFID cards. The RC522 is a highly integrated transmission modules for 13.56MHz communication, it supports ISO 14443A/MIFARE mode. The RC522 utilizes an outstanding modulation and demodulation concept completely integrated for different kinds of contactless communication methods and protocols.