The term generally signifies the Western orchestral instrument, but may also refer to the Chinese woodblock.

The dimensions of this instrument vary, although it is either a rectangular or cylindrical block of wood with one or sometimes two longitudinal cavities.

[2] Alternatively, a rounder mallet, soft or hard, may be used, which produces a deeper-pitched and fuller "knocking" sound.

It is made in various sizes and is often used in Buddhist chanting, in China as well as in other Asian nations including Japan, Korea, and Vietnam.

Typically used in sets of four different pitches, they are sometimes called "skulls" by jazz players because of their globular shape.