Get the extended range and multi-drop capability of RS-232 or RS-422/485 from the USB port of your PC. 2000VDC optical isolation protects PCs and laptops from dangerous surges and spikes on the network. Windows automatically configures the serial outputs as additional COM ports. Compatible with your Windows application. USB 1.0, 1.1, and 2.0 compatible (12 Mbps) .No power supply required (powered from USB bus).