Gehu is made of mahogany and rosewood, with a total length of 170 cm. The headstock is carved with a faucet, the stem is inserted into one side of the drum, and the surface of the stem is provided with an arc-shaped fingerboard.

The drum is round, 37 in length and 38 cm in outer diameter of the front opening.

Python, horse or sheepskin. Rear audio window. Leather surface tension is adjustable. Set four axes, Zhang four strings. It can be played with a low-hued bow or with a cello bow.

The vibration of the strings passes through the piano barrel through the outer bridge, and is connected to the inner bridge in contact with the python skin. At the same time, the amplitude is amplified by the principle of leverage, so that the volume can be guaranteed. Because of the pure python skin sound, the timbre has a good connection with the high, second, and middle hu, and it is not abrupt in the Chinese orchestra. Compared with the cello and double bass, it has better orchestra integration. Gehu's commonly used tunings are C, G, d, and a, and the range can reach five octaves.

In the 1970s, it was developed into a circular square cylinder synergistic type and a full-plate type gehu.

The former co-vibration drum is a combination of diaphragm plates, and the back of the python skin is affixed with a tungsten board, which makes it sound solid and loud; The straight lever of the lever makes the three boards vibrate together, and the sound is thick and deep.

However, after years of performance demonstration, the first generation 58 is the best in tone, performance, performance and appearance. The diameters of the python skins of Gehu and Bass Gehu are 33 cm and 50 cm, respectively. The raw materials are the same as those of Erhu, and there is no need for special "giant pythons".