All Legacy Mobile I/O ULN-2's can be upgraded with a 2d Card. The 2d card ships with a new ADAT/Optical I/O board that adds Optical I/O to the unit as well as a new back panel.

If you are a very technically inclined user, you can do your own field upgrade of your unit, but please be aware that is is a somewhat complex install, and that field installs do not carry a factory warantee for the 2d Card. Before choosing to do the field install, please watch the instructional video for your unit (Streaming Install Video for ULN-2 -or- Download Install Video for ULN-2) and evaluate if it is within your capabilities.