Connects any RS-232 serial device with DTE D-B9 to PC with DB-9 serial port. This null modem cable also allows you to transfer files between two computers using its DB-9 serial port as well as all RS-232 DTE to DTE connections. Works with file transfer software that comes free with MS DOS & Windows and Laplink's software. QVS cables are UL listed, have matched impedance, PVC jacket, molded ends with thumbscrews and inner hood soldered 360 degrees to the connector for complete end to end shielding.