Yak

The yak (Korean: 약) is a small flute used vertically, which has three holes and is used in court music. It is a wind instrument, a small carved instrument, which was imported from China in 1116 (the eleventh year of Goryeo's King Yejoing period). This wind instrument was called a wiyak because it was made of reeds, not bamboo. It is currently made of thick yellow bamboo. It is used for Aak (hanja: 雅樂), and according to the instrument classification method, it belongs to Jukbu (竹部) or Gongmyeong instrument (共鳴樂器).