The chromatic zither is really a professional instrument. Made famous by the film ‘The Third Man’ – Anton Karas. It has 30 – 45 strings and of these a few lie over the fretted board and serve to produce the melody – the remainder being open strings used for the accompaniment. The left-hand thumb stops the strings while the right- hand thumb, with a plectrum, plays them. Meanwhile the three larger fingers of the left hand pluck the accompaniment. To play it, the instrument is placed on the knees.