IC485S [IC485SIS] converts RS-232 serial interfaces to RS-485/422 serial interfaces for trouble-free data transmission. This 2-in-1 converter converts RS232C to either the RS-485 or RS-422 interface, and is DCE/DTE mode selectable at the flip of a switch, making it easy to change line signals!The RS232 serial interface converter offers several convenient features including mode selection, point-to-point multidrop configuration and RS 485/422 monitor mode, and is constructed of high grade plastic for enhanced durability. The converter supports connections of up to 4000 ft, with data transfer rates of up to 1MB/sec.Suitable for a broad range of operating environments, this adapter includes an optional 9V power adapter or can draw power on its own, and is backed by StarTech.com's 2-year warranty and FREE lifetime tech support.