The H2-SERIO-4 is a DIRECTLOGIC DL205 communication module supporting Do-More protocol, Modbus RTU and ASCII. It features 3 ports including (2) RS-232 (RJ12) and (1) RS-422/RS-485 port(s), designed for use with Do-More H2 series PLCs or H2-EBC100-based systems connected to PCs.