125KHz EM4200 RFID Key Tag for Access Control can be called 125KHz EM4200 RFID Key chain,the tags are now adored by a number of people as they weigh light and are portable to bring it everywhere. It is becoming a fashion stuff these days and making our life more easier. As the technology is moving with a rocket speed and nothing is left untouched with the technical advancement so implies for the RFID ABS Keychain.High quality EM4200 125KHz Custom RFID key Tags can be read and writable.