It has no pedals and is a diatonic instrument, which limits much of the traditional music to a major key and its related minor. There are however several methods of making semitones. One is to shorten the strings at the lower end by pushing a small peg between the strings. Another method is to shorten the strings at the top end by means of a metal key which is held between the fingers of the dominant hand. However, more recently, harps have begun to be constructed with the addition of levers to overcome this limitation, and many players are now using levered harps.