Sometimes called a ba wu flute, a Chinese wind instrument popular in Yunnan province. Although shaped like a flute, it is actually a free reed instrument. It has a cylindrical bore, made of a tube of bamboo closed off at one end by a natural node. It has 7 finger holes (including the thumb hole) and a small harmonica-like metal reed in the embouchure hole. It is played in a transverse (horizontal) manner. It has a pure, clarinet-like timbre and its playing technique incorporates the use of much ornamentation, particularly bending tones. When blown just right the reed couples to the resonance of the flute and to the mouth cavity.

The Vietnamese bawu is almost identical to the Chinese version, although their tunings and scales are do differ from each other. The Vietnamese bawu has 6 finger holes and a similar brass reed.