The er-squeak shape is similar to the pipa, and more similar to the Dinghan of the Dai nationality. Most of them are made by the performers for their own use, so the specifications and sizes are different. The total length of the piano body is mostly about 45 cm, the small one is only 30 cm, and the larger one can reach 60 cm. There are two kinds of postures, sitting and standing.

The shape of the erzhi is similar to the pipa, and more similar to the Dinghan of the Dai nationality. It can be played in both sitting and standing positions.