Features:
- Self-powered from USB.

Complete includes:
- One USB to RS485 module
- One additional SN75176 BUS TRANSCEIVER

Links:
Manual - http://www.sigma-shop.com/manuals/usb_rs485_manual.pdf
Drivers - http://www.ftdichip.com/Drivers/VCP.htm

Drivers are available to work with the following operating systems :
Windows Vista x64, Windows XP x64, Windows Server 2003 x64,
Windows Vista, Windows XP, Windows Server 2003, Windows 2000,
Windows ME, Windows 98, Linux, Mac OS X, Mac OS 9, Mac OS 8,
Windows CE.NET (Version 4.2 and greater)

The drivers listed above are all available to download for free from the FTDI website. Various 3rd Party Drivers are also available for various other operating systems - see the FTDI website for details.