The , sometimes romanized as or , is a Japanese aerophone, an end-blown bamboo flute, crafted from root sections of bamboo. The bamboo root is cleaned and sanded, resulting in a surface patterned with many small, circular knots where the roots formerly joined the stalk. The same part of the bamboo plant is also used to produce the but, unlike the , the 's inside (bore) and outside surfaces are left unlacquered, and an inlay is not used in the mouthpiece. The membranes at the nodes inside a bore are generally left more intact than those of a , though older also share this trait. Together, these characteristics make for a visibly and audibly raw and organic instrument. are sometimes referred to as , meaning "without [a paste made of clay and lacquer, used to smooth the bore on modern ], one-piece"; are not cut in two pieces for crafting or storage, unlike modern that are used as musical instruments. have four holes down the front for fingers and one hole on the back for the thumb of the upper hand. The instrument is capable of a range of at least two octaves, and more if the instrument is well-crafted and in the hands of an experienced player; they can be fashioned to any length, suitable bamboo permitting, with longer instruments having their frequency range shifted proportionally lower. are typically longer than other variations of the , and almost always thicker and heavier. The techniques for playing the are similar to techniques, although the sound resulting from is more fragile and possibly less well tuned to musical scales than are modern, refined (, or tuned ) . The angle of the , or blowing edge, of a is closer to perpendicular to the bore axis than that of a modern , but this is mostly a choice of the maker depending upon the size of the bamboo. Older and also share this trait, though unlike they usually have an inlaid blowing edge. This property, along with the unlacquered bore, results in a rough and breathy timbre. Because of its extremely natural construction, the is commonly used for (blowing Zen meditation). Playing traditional is generally only attempted by highly skilled musicians, since the blowing and fingering techniques required for have to be altered considerably. Since are not generally tuned to a standard musical scale, they do not commonly accompany other instruments.