What is the name of ktv clapping metronome?

The sand hammer is a rocking musical instrument, also called sand ball. A rhythmic percussion instrument originated from South American Indians. The traditional sand hammer uses a spherical dry gourd filled with some hard seeds or crushed stones, and the original slender neck of the gourd is used as the handle. When shaking, the hard particles hit the wall of the gourd to make sound. There are also wooden, ceramic, rattan and plastic similar-shaped sand hammers, which contain beads, lead pills and other things. Usually, each hand holds a shake.