OT: Plumbing; what is 'track pipe"..?

[beergears]

We are getting a gas fireplace insert installed and the plumber's estimate part reads:

1/2 track pipe qty: 40 rate 4.28 (price/ft, I assume) total $171.2

Is track pipe a flexible line, and why is he running that form the mains, instead of good old back pipe, rated for gas?

I know he needs a small flexible section when arriving at the unit, but...

 

[Bowtiebrewery]

I'm assuming this is running Natural Gas or LP right? I believe depending on code in certain states you must run that yellow flex line now... When we had our gas range put in we wanted to run Black Pipe from the outside in and the guy told us that he had to use the flex line... It cost us much much more than $171 though we had to run almost 100 feet of it...

 

[beergears]

I'm assuming this is running Natural Gas or LP right? I believe depending on code in certain states you must run that yellow flex line now... When we had our gas range put in we wanted to run Black Pipe from the outside in and the guy told us that he had to use the flex line... It cost us much much more than $171 though we had to run almost 100 feet of it...

Thanks.

Yes NG.
He is only running from, roughly, the furnace area to the living room, so, yes that's 40 ft there.

Why the new fancy lines though, which can be easily damaged, and prone to leak, as I read on it?

EDIT: Probably local code... PEX, trac pipe, houses are turning into sphagetti dinners!

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