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There usually ok if left alone? I have to connect a new toilet on to this was wanting to leave all as is. And just put a street elbow into the top 45Yes, many times in the past.
They were available for Hepsleve, then Supersleve (slightly smaller O.D clay pipe) but not for traditional glazed collar pipe as the surface wasn't smooth enough and diameters varied.
Reply to the thread, titled "Clay to 110mm plastic soil pipe fitting" which is posted in Boiler Advice Forum on Plumbers Forums.
We recommend City Plumbing Supplies, BES, and Plumbing Superstore for all plumbing supplies.