Pro Tools Audio Interface Digital Options003, 003 Rack, 003 Rack+, Digi 002, and Digi 002 Rack include S/PDIF and ADAT digital I/O.Eleven Rack includes S/PDIF and AES/EBU digital I/O.Mbox (3rd generation), Mbox 2, Mbox Pro, and Mbox Pro 2 include only the S/PDIF digital option.All digital outputs are active at all times, so you can actually send digital audio to different digital devices simultaneously at mix time.