Vibraslap

vi·bra·slap

A vibraslap is a percussion instrument consisting of a piece of stiff wire (bent in a handle-like shape) connecting a wood ball to a block of wood with metal "teeth" inside. When the percussionist holds the handle in one hand and strikes the ball (usually against the palm of their other hand), the metal teeth vibrate against the wood block, causing a distinctive rattling sound. The instrument is the modern descendant of the jawbone.