The setar is a long-necked, four stringed instrument which has a soundbox covered with thin wood. It is a descendent of the ancient Iranian tambur of Khorasan, which is credited with being the ancestral form of nearly all lutes now known in the East. The setar originally had only three strings. The fourth was added by the great mystic Moshtaq Ali Shah. The setar itself is more adaptable to spiritual music. The left-hand technique for playing the setar is nearly identical to the tar techinque, but, instead of a plectrum, the fingernail of the right-hand index finger is used. This technique for playing, as well as many other aspects of the Persian setar, including the shape of the instrument and the peg arrangement, were adopted in India and resulted in the Indian sitar.