Piri
The piri is a Korean double reed instrument, used in both the folk and classical (court) music of Korea. The "piri" was originally a musical instrument in the western part, and has already been used in Goguryeo and Baekje since the period of the Three States(hanja:三國時代). It is made of bamboo. Its large reed and cylindrical bore gives it a sound mellower than that of many other types of oboe. In the typical piri, there are eight finger holes on the bamboo body. Seven of the finger holes are on the front and one is on the back  for the thumb. There are four types of "piri": There are different types of piris because each is suited for a different type of music and use. The Hyang piri is the longest and most common out of all piris. Because of its loud and nasal tone, it usually plays the main melody in an ensemble. The se piri is the smaller, thinner, and much quieter one. Additionally, because of its quiet tone, it is used along with voices or soft stringed instruments. The Dang/Tang piri is wider and is similar to the Chinese guanzi instrument. Additionally, the dae  piri is a modernized piri, with keys and a bell, looking much more like a western oboe. In general, the method of playing the "piri" is to sit upright, pull the chin slightly, straighten the back to make it easier to breathe, hold the flute in both hands, and bite it in mouth. Piri is thought to have been introduced to Korea from a country bordering west of China before Goguryeo period. According to the "Book of Sui", piri was also known as "gagwan" (가관; 笳管), and it originates from Kucha. During the reign of King Yejong of Goryeo dynasty , another double-reed cylindrical instrument was imported from Song dynasty China, and to disambiguate, the former was named "hyang piri" and the latter "dang piri". "Se piri" is smaller than "hyang piri" but has the same structure and range. "Se piri" appears to be invented much later than "hyang piri". The piri's equivalent in China is the "guan" (also known as "bili"), and its counterpart in Japan is the "hichiriki".