Hello. What do you call this opening where the tube on the wall goes?
The copper tubing is penetrating the wall. 
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Penetration trough walls…Applies to everything from plumbing, electrical, HVAC etc…
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A hole? 
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ah that would be Your basic hole in the wall …what You have pictured there are multiple holes in the wall with pipes in them…
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Keep it simple Kevin… 
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Thank you and apologize for such a newbie question. I thought there is a particular term where a tube goes on a hole. Thank you again.
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No problems with “newbie” questions Marc. “Penetrates” is how I describe and the term I use in my reports!
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No problem Marc, better to ask than not.
Could it be you’re thinking of conduit or a protective sleeve?
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Pipe penetration hole would work, too, Marc.
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Larry, you’re getting graphic and the forum police will be here soon to criticize and threaten to leave… 
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The rings that cover those holes is called an escutcheon
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Promise, Thomas? 
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Like Brian said above, it’s a pipe penetration and missing the trim called the escutcheon.
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Welcome to our forum, Bobby!..Enjoy! 
What is that? Did you mean annular space?
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