This module is used to communicate between your Arduino or favorite MCU with RFID technology. It uses NFC (Near Field Communication), a type of wireless communication used in many applications, even in some new phones. The kit comes with two different types of passive tags: 1x round tag, 1x card type tag. The tags are passive, which means that you don't need a battery to run, they use the energy from the reader to send the information to it. The antenna on the reader allows to communicate with the tags to a maximum distance of 40-60mm. The reader communicates with the MCU or Arduino through SPI communication It can be used for applications such as for personal door access, etc. MF RC522 using advanced modulation and demodulation concept completely integrated in all types of 13.56MHz passive contactless communication methods and protocols. Support 14443A compatible transponder signals. The digital part handles ISO14443A framing and error detection. In addition, support fast CRYPTO1 encryption algorithms, terminology validation MIFARE products. MFRC522 supports MIFARE Series higher speed non-contact communication, two-way data transfer rates up to 424kbit/s. As a highly integrated 13.56MHz card reader new family of chips, MF RC522 MF RC500 and MF RC530 and there are many similarities, but also have many features and differences. It is between the host communication using SPI mode, helps to reduce connection, reduce PCB board size and cost. MF522-AN module adopts Philips MFRC522 original reader circuit chip design, easy to use, low cost, suitable for equipment development, development of advanced applications like reader users, the need for RF card terminal design/production of the user. This module can be loaded directly into a variety of readers molds. Module uses voltage of 3.3V, through the SPI interface simple few lines can be directly connected to the user any CPU board communication module can guarantee stable and reliable work.