The Guitaro made by Oscar Schmidt and the ChromAlin made by Rythm Band Instruments, both are a variation of an autoharp. In this regard both are also considered a Chorded Zither. The Guitaro and the ChromAlin have only 24 strings and 15 chord bars. Plays in 5 keys. They are similiar in shape although the ChromAlin is shaped with more rounded edges. Both use a resonator which is mounted on the back of the bout, no soundhole on the front. But there were few that don't have resonators with a soundhole on the front. I think the latter were made for catalog companies for less money. I don't ever see many for sale. So anyone who has one let me know.