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StarTech ICUSB2324 4 Port USB to RS232 Serial DB9 Adapter Hub
Add four additional RS-232 serial ports to any computer with a free USB port
Provides serial connectivity to legacy free systems lacking RS-232 serial ports
Supports wakeup and power management modes
Bus powered no external power adapter required
Easy Plug-and-Play installation
Fully compliant with USB 11 specifications and compatible with USB 20