Fatek M series Main Unit , Advanced Version, 16x16 DI/DO, Transistor SOURCE (PNP) Output, Maximum I/O: 512/128, 1 10/100 Base-T Ethernet Port, 2 RS-485 Terminal Port (Master/Slave Function), 1 USB Type-C (2.0) Port, 24 VDC. IoT Compatible. Datalogger.