The trunk is made in the shape of a bowl, being different from that of Kokyu in the main islands of Japan (in olden times, the trunk was made by splitting the nut of coconut palms into halves), and the leather of a python is used for covering the trunk as those for Sanshin (Okinawan traditional three-stringed instrument).
胴は内地の胡弓と異なって椀型になっており（古くは椰子の実を二つに割って胴にした）、三線と同様にニシキヘビの皮を張る。