5' USB to RS-232 DB9 Serial Adapter Cable – Serialio.com
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StarTech.com USB to Serial Adapter - Null Modem - FTDI USB UART Chip - DB9 (9-pin) - USB to RS232 Adapter - Add a Null Modem RS232 serial port to your laptop
StarTech.com 10 ft DB9 RS232 Serial Null Modem Cable F/M - SCNM9FM - Serial Cables - CDW.com