This large 25-6 zither was a compromise. While it shunned the more creative gadgetry, it attempted to increase its musical flexibility by adding in all the sharps and flats of the fully chromatic scale, and as well two more 4-string chord groups that allowed it to be played on the keys of C major, D major, A major, and (with one retuned string) D minor and E minor. It is difficult to play however, as there is nothing to visually differentiate the 'black-key' strings. There was a follow-the-dots tablature available as a stiff card that slipped under the strings. That allowed for fairly mindless playing!
This instrument was donated by Ed and Judy Green of Carrollton, Texas.