Contactless USB NFC ACR122U RFID Smart Reader Writer + SDK + 5M1 IC Cards Read/write speed up to 424 kbps Built-in antenna for contactless tag access, with card reading distance of up to 50 mm (depending on tag type) Supports ISO 14443 Type A and B, Mifare, FeliCa, and all 4 types of NFC (ISO/IEC 18092) tags Supports new Mifare Ultralight C (via pseudo APDUs) and Mifare Plus SL1 (4 Byte UID, via pseudo APDUS) and SL3 Supports all 3 modes of NFC: reader, card emulation and peer-to-peer modes