The Omron C200H-LK202-V1 is a Host Link Unit (RS-422 communication module) for the SYSMAC C200H series PLC. It serves as a robust serial communication interface for connecting the PLC to host computers, HMIs, or other industrial devices over longer distances compared to RS-232C. Supporting the Host Link (C-mode) protocol, it enables program upload/download, data monitoring, and remote control.