I bought some of this the other day without looking at it. When I opened the roll it was clear this is a lot less product than blue smurf. The stuff is flimsy and has nasty mold marks in it, clearly not an article 362 product, yet it costs exactly the same. If you do bite, be sure you get some orange connectors. This stuff is so soft it jams up in a blue fitting.
Study Guides for VDV / Structured Cabling Installers
That was what I thought but the orange is definitely an inferior product that is lighter (thinner wall) and does not have the same fit and finish. It is not identified as "ENT" or any other "U/L" listing as far as I can tell. There is some unintelligible writing on it that I can't read.
We've got a ton here the IT guys use for fiber, but I'd never really looked all that closely, I just assumed it was plenum-rated ENT, as orange generally indicates plenum and it sure looks like ENT. You're right that the writing is illegible, it's insane...
I think I can make out: CONDUIT 1" PLENUM CORRUGATED (ETL) UL ####
It was originally designed as inner duct for pulling fiber into existing banks of 4" conduits. Three or four of these would be pulled in to create separate compartments. The walls were thinner since it didn't really need much in the way of crush resistance.
Inner duct eventually migrated indoors as IT guys liked to use it for added protection for fiber cable. It's not necessary, but some people just prefer it. Since it was IT guys making these decisions, the popularity of using inner duct took off dramatically and Carlon was one of the larger manufacturers of it. They came out with plenum versions, smooth or corrogated, multiple colors, etc.
Eventually, this popularity extended into the low-voltage industry everywhere. Speakers, CATV, phone, you name it. Carlon seized this opportunity by developing a completely separate line of products for this use.
So, in reality, this was never really meant to be directly compatible with ENT at all. It was a separate product line that had much less stringent requirements.
Your tag line says it all, the guy at the home depot did say it was the same stuff. Since it costs more, the 25' roll I bought will be my last. I have no problem "reidentifying" my low voltage run with tape.