A vertically-held flute with an open mouth on top that has an angled cut in the front for producing a sound. Most shakuhachi, literally one shaku (24.6 cm) and eight sun (2.4 cm) long, are made from bamboo with three nodes, though some in the Shōsō-in ones are made of other materials, like serpentinite stone, and crafted to imitate the bamboo shape. Shōsō-in shakuhachi have five finger holes in front and one in back, one more than modern ones, with only four finger holes in front.