Zhamunian is mostly divided into four specifications, its size and use are as follows

Bass Jamunian
The body is 126 cm long, the sound box is 48 cm long, and the face is 20 cm wide. For formal performances only.

Year of the Great Jamun
The body is 111 cm long, the sound box is 27 cm long, and the face is 16 cm wide. For normal performance.

middle zhamun year
The body is 103 cm long, the sound box is 27 cm long, and the face is 14 cm wide. It is also used for normal performance.

little jamunian
The body is 81 cm long, the sound box is 23 cm long, and the face is 13 cm wide. Designed for children to play. In the previous Jamun year, most of them were made by Tibetan craftsmen. After the 1960s, many manufacturers of ethnic musical instruments in the mainland also began to manufacture Zhamunian. The resonance box was mostly covered with python skin, and the back of the piano was not engraved with vertical rib patterns or glued with wooden strips, and the body of the piano was easy to slide when playing.