Here is a definition of “corrugated cable” from the web site of Huber Suhner, a company that makes cables:

http://www.hubersuhner.com/p-rf-cab/p-rf-cab-info/p-rf-cab-d...

“Coaxial Cable with corrugated outer conductor. Even the outer conductor is a tube, the corrugation makes the cable flexible. Very often used in telecommunication application as jumper and feeder cable.”

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