A clapper performed with one hand. Also called tanban. The thick side is made of two wooden plates fit together, and the thin side is made of one. They are loosely tied together by a piece of string. This string is draped over the thumb of the left hand, and the thin side is held by the remaining four fingers. By rotating the wrist, the lower end of the thick side is hit against by the thin side. This is an essential rhythmic instrument used in all types of ensemble and in the accompaniment of traditional theater. Most often a single player sounds this clapper in the left hand, while striking a drum in the right.