StarTech.com USB Adaptor Cables - StarTech.com ICUSB2321FIS, This ICUSB2321FIS 1-Port FTDI USB to Serial RS232 Adaptor Cable with Optical Isolation from StarTech.com converts an available USB 1.1 or 2.0 port into an RS232 DB9 port that can be used to connect, monitor and control your serial devices.The USB to serial adaptor features integrated optical isolation circuits and surge protection to protect your critical, sensitive control equipment against electrical damage, making it a viable solution for costly industrial serial devices.The versatile FTDI chipset also supports COM retention, additional customisation/features, and compatibility not offered by most other solutions. Broad operating system compatibility including Windows®, Windows CE, Mac OS and Linux, makes this product easy to integrate into mixed environments.It is backed by a 2-year warranty and free lifetime technical support. StarTech.com ICUSB2321FIS USB To RS232 DB9 Serial Adapter Cable With Isolation