The hollow metal ring with small metal balls in it has changed from a tool for soliciting business on the street to a musical instrument used in performance.
a hollow metal conductor that provides a path to guide microwaves; used in radar.
a hollow metal rod with a heavy rubber tip or tips that is wielded and twirled by a drum major or drum majorette.
"bell:a hollow metal instrument, usually cup-shaped with a flared opening, that emits a metallic tone when struck."
Comprising a hollow metal-ball with orifices. The ball is joined to piston and cylinder. Press the piston, water jets out of the orifices in all directions.
An assembled hollow grounding equipment including grounding lead-out wire features that it is made up by fastening a lead-out wire to a hollow metal ball.
"Spinning In metalwork, a technique for making hollow metal utensils and artifacts."
