This is the detail page for one of over 225 audio interfaces covered in The Computer Audio Interface Guide, which also lists where to buy this interface used.
4 analog in (2 combo XLR/TRS or 4 TRS), 4 analog out (TRS), ADAT I/O, S/PDIF I/O, built-in effects, multiple units can be networked, bus powered, 2 headphone outs (Summer 2006).