What is this pipe/ tube?

[Stutsman]

I am assuming this is a USA forum, so I will ask- I have a water main feed tube/ pipe, black in color, feels exactly like HDPE, is 1 3/8" ID (1.375) and 1.900" OD., same as 1 1/2" iron pipe. It was installed in 1971/72 in Los Angeles County. I need to adapt to it to install a new water meter/ backflow valve, 1 1/2" in size. I do not want to dig up 500 feet of driveway to replace it. I could not find any reference to it as far as what it is. The closest I can get to a fitting is 2 different parts in the Ford catalogue. Any ideas what this is? Any and all suggestions are welcome. Thanks in advance.

 

[WC1]

It's a frequent problem on here, you'd be forgiven for thinking that it's a us site. Most of us are uk. But post up a picture or 2 and you may get a bite. Good luck.

 

[Timmy D]

It's a frequent problem on here, you'd be forgiven for thinking that it's a us site. Most of us are uk. But post up a picture or 2 and you may get a bite. Good luck.

And I’ve just noticed we’ve got a USA advice forum.

Post up some pics, let’s have a look.