1Input Signal: 4 input ports, supports up to 115,200bps, selectable auto manual switching by external switch, selectable primary secondary input by external switch. 2Safe Operation: The marine serial line splitter supports over voltage protection, over current and surge voltage protection, reverse input and over current protection. 3Practical: There are wiring instructions at the wiring area to prevent wiring errors, and pluggable screw terminals for quick and easy installation and diagnostics. 4Design: Galvanic isolation of Each output group, input, main circuits and power, selectable RS232, RS422, Ttl on 8 output port. 5Durable Material: Made of aluminium alloy shell, anti rust treatment, will not be oxidized and corroded by seawater or air, long term durability.