RS232 to RS485/422 converter, 2500V isolation, 9VDC. The Model485P is a high performance, multifunctional RS-232/485/422 interface converter. The product configure out connect power, optic-electrical isolation more than 2.5KV. Have small volume, far transmission distance, high rate, steadily performance and so on. It is abroad used in industry control system, It is an interface convert product that have good between performance to price. Adopt it..