Wooden fish come in many sizes and shapes, ranging from 150 millimetres (5.9 in), for laity use or sole daily practice, or to 1.2 metres (3.9 ft) for usage in temples.

Wooden fish are often (in Chinese temples) placed on the left of the altar, alongside a bell bowl, its metal percussion counterpart.

One Buddhist legend says that a monk went to India to acquire sutras but on his way he found the way blocked by a wide, flooded river.

Its simple request was that on the monk's way to obtain sutras, he should ask the Buddha to guide the fish on a method to attain Bodhisattvahood.

When proceeding with various duties (such as eating, lectures, or chores), a monk and a supervisor utilize the instrument to call all monastics to go to their tasks.

Therefore, it is to remind the chanting monks to concentrate on their sutra[7] where recitation of texts is necessary[2] and the sound symbolizes wakeful attention.

[2] In Confucianism, the wooden fish is struck at specific intervals to signify certain stages of ceremonies at temple.

In Japan, wooden fish are called mokugyo (kanji: 木魚; hiragana: もくぎょ), and some huge specimens found in Buddhist temples weigh more than 300 kg.

Often the mallet used to strike the fish has a rubber coated tip to provide a muffled, but clear sound when struck.