The Harmolin is a unique zither that allows one to play chords by selecting only the strings tuned to the notes of the desired chord. It is similar to an autoharp in this regard, but achieves its purpose in a very different manner. The metal grate has notches that dictate which strings are plucked by the roller pick. These notches are arranged in 15 rows, and the grate can be set in 12 positions, for a total of 180 chords (in contrast with the largest autoharps, which only have 21 or 28 chords). The Harmolin also features a damper bar, so chord changes can be quickly accomplished with it.
