Hi,
apparently it's a pocket sized sound module
I found info at http://www.ketron.it/news/index.asp?idNews=18

If the sounds are similar to the sd1, it would give me the opportunity to tweak my omb styles and use them either with the sd1 at home or have the portability of the sd2/omb/laptop setup. Also saves me trying to convert all my yammie styles to ketron format.

best wishes
Rikki