Onboard Original FT232RL and SP485EEN chip. Fast communication, stable and reliable, better compatibility.Onboard unibody power supply isolation, provides stable isolated voltage, needs no extra power supply for the isolated terminal Onboard unibody digital isolation, allows signal isolation, high reliability, strong anti-interference, low power consumption.Onboard TVS (Transient Voltage Suppressor), effectively suppress surge voltage and transient spike voltage in the circuit, lightningproof & anti-electrostatic Onboard self-recovery fuse and protection diodes, ensures the current/voltage stable outputs, provides over-current/over-voltage proof, improves shock resistance Onboard 15KV ESD isolation protection and 600W lightningproof & anti-surge protection.Onboard 120R terminal resistor on the RS485/RS422 ports, enable by default, configurable by jumper 3 LEDs for indicating the power and transceiver status.Industrial rail-mount ABS case design, small in size, easy to install, and cost-effective