a hollow metal conductor that provides a path to guide microwaves; used in radar.
"Spinning In metalwork, a technique for making hollow metal utensils and artifacts."
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.
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.
"bell:a hollow metal instrument, usually cup-shaped with a flared opening, that emits a metallic tone when struck."
a hollow metal rod with a heavy rubber tip or tips that is wielded and twirled by a drum major or drum majorette.
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.
