optoelectronic isolated USB/MPI, Siemens S7-300/400 PLC Programming adapter cable, 3 meters, with communication indicator, can replace Siemens 6ES7 972-0CB20-0XA0, automatically adjust the communication speed from 19.2Kbps to 115.2Kbps for the PC port, automatically adjust the communication speed from 19.2Kbps to 187.5Kbps for the MPI interface.