Andrew Mawson coughed up some electrons that declared:

Tim, East Sussex so not too many miles away. But is that stuff
connectable to brown 100mm drain pipe?

That I don't know Andrew. If it's not exactly the same (so that a coupler
would work), I suspect one might plug into the other well enough that a bit
of mastic or silicone would finish it off.

If you do decide to go for it, I could order and you collect the length you
want (Robertsbridge or Pembury) or you order and I'll come to you with cash
and take a length off your hands.

Cheers

Tim