The ACOS3X eXpress Microprocessor Card from ACS contains a powerful processor with a large EEPROM memory size of up to 256KB and is fully compatible with other members of the ACOS3 product line. Similar to ACOS3, ACOS3X enables a single card to support various applications. ACOS3X also supports mutual authentication, secure messaging and key diversification, in order to provide utmost security for any application.