Information from the manufacturer:
The 192 I/O is all about sounding phenomenal — rivaling similar products more than double its price. On top of offering up to 16 channels of analog and digital I/O, the 192 I/O lets you take your pick over a flexible range of connection types. And with 24-bit/192kHz A/D and D/A operation, the Digidesign 192 I/O is your one-stop choice for getting your tracks into the world of Pro Tools|HD. An expansion port onboard lets you directly connect another 192 I/O or its little brother the 96 I/O. For clarity and precision, at an unbeatable value — it's got to be the Digidesign 192 I/O.