Black Box Industrial USB 2.0<->RS-232 DIN Rail Converter - serial adapter

With these converters, you can add COM port(s) to your PC. The converters protect against surges, too. They provide 15-kV ESD surge protection against spikes and ground loops. Plus, the converters support data rates up to 12Mbps for USB and 460.8kbps for RS-232, and they use all RS-232 handshaking.