Greetings,
I am getting ready to put a bathroom in the basement of my 18yr old house. Plumbing was roughed in by builder. The picture I attached is of what I think is the shower drain but I have never see. Anything like it before. There is a 2" cast iron pipe with a rubber doughnut around it surrounded by another cast iron collar. What is the collar for and is this actually a shower drain? Thanks in advance for your responses.