USB 4-Port Serial Adapter - USB 2.0 to DB-9 Port RS232 with FTDI CHIP - Coolgear
StarTech.com 1 Port USB to RS232 DB9 Serial Adapter Cable - M/M - ICUSB232V2 - Serial Cables - CDW.com
USB 2.0 To Serial DB9 Male (9 Pin) RS232 Cable Adapter - Sabrent
USB to RS232 DB9 Serial Adapter Cable - Serial Cards & Adapters | StarTech. com
Sewell InstaCOM USB to Serial Adapter — Sewell Direct
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Amazon.com: Plugable USB to Serial Adapter Compatible with Windows, Mac, Linux (RS-232DB9 DTE Male Connector, Prolific PL2303HX Rev. D Chipset) : Electronics