The shamisen is a three-stringed traditional Japanese instrument with a long, fretless neck and a square body traditionally covered with cat or dog skin (though synthetic materials are now common). It is played with a large, fan-shaped plectrum called a 'bachi.' The shamisen has a distinctive percussive sound because the bachi strikes both the string and the skin of the body simultaneously. A unique feature is the 'sawari'—a slight buzzing sound caused by the lowest string touching the neck, which is considered a mark of beauty in Japanese aesthetics. It is used in everything from Kabuki theater to modern rock fusion.