A couple of days ago, this is an old existing cast iron drain line that has been eroded and full of tree roots. Mock Plumbing installed a 4” test tee where sewer line exits slab for a clean out.
Mock Plumbing always uses 4” schedule 40 when running their sewer lines. Most other plumbing companies use a thin wall sewer pipe which is only half the strength of schedule 40. Another Happy Customer!