The fine grain, which is called "grass splitting force" in Korean and commonly known as "pipe" in the folk, is popular in Yanbian Korean Autonomous Prefecture of Jilin Province and areas inhabited by Koreans.

The fine pitch is divided into three types: soprano, alto and double pitch.

The traditional high-pitched fine pitch can only play one mode. Later, the instrument maker opened a small hole with a key in the upper right corner of its sixth sound hole, so that the sound range of this instrument reached two and a half octaves. , and also has the function of transposition. The function of the alto fine pitch and the treble fine pitch is similar, the difference is that the alto fine pitch is one octave lower than the high pitch fine pitch. Compared with the former two, the double-pipe fine horns are connected side by side with two high-pitched fine horns of the same size and pitch. Each horn is equipped with a whistle. When playing, you can either play a single pipe to make a single note, or you can hold two whistles and blow two notes at the same height. In addition, the double-pipe fine pitcher can also play chords of thirds, fourths and fifths, and the volume is much higher than that of the single-pipe fine pitcher, the tone is melodious and beautiful, and the playing skills are more difficult.

In addition to the high-pitched fine pitch, there are also the middle pitch of the alto and the large pitch of the bass in the grass power of the Korean nationality. The alto pitch is one octave lower than the fine pitch, and the bass pitch is one octave lower than the alto pitch, with a total range of D—g3. After the reformation and key addition by Master Wu Zhongfu, in addition to maintaining the original unique timbre, the volume of the middle and bass parts of the Korean national band has been significantly strengthened, and the expressive force of Korean folk music has been enriched.