The MTQ-H5-B02-SP is a modbus TCP serial server expansion module device made by Multitech. It features 4 serial ports that can be used with RS-232, RS-422, and RS-485 communication protocols, and is also compatible with Modbus RTU/ASCII protocols. Each port is isolated from the others and also contains surge protection. The module also offers Ethernet redundancy which can provide a failover connection from a primary Ethernet connection to a secondary Ethernet connection in the event of a primary connection failure. The module is also certified for use in hazardous locations for both the US and Canada.