My house was built in early 70's.. No plastic.. I'm putting in a new sink and had to remove the wall pipe that goes into the wall.. I needed a longer one.
It seem where it goes in behind the wall into the plumbing there was some type of gasket as pieces of it fell out when I removed the pipe.. I can tell with my finger that there is a ridge in there where a gasket could fit..
What would I call it at Home Depot or should I just load it up with silicone?
It is a 1 1/2 " waste pipe..

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