Wiktionary
flexatone
n. A modern percussion instrument consisting of a small flexible metal sheet suspended in a wire frame ending in a handle.
Wikipedia
Flexatone
The flexatone or fleximetal is a modern percussion instrument (an indirectly struck idiophone) consisting of a small flexible metal sheet suspended in a wire frame ending in a handle. Used in classic cartoons for its glissando effect, its sound is comparable to the musical saw.