I used these to replace a pop-up waste on my bath. The plumber replaced the pop-up waste with a new unit but failed to seal the new unit in, so when the bath was used, it leaked. I actually said to the plumber, when he wa on the job, that I had hired somebody as was worried about replacing units that fit into waste pipes correctly, as wanted the job done properly! Contacted them to arrange for them to come out and rectify and the same plumber was booked to come back to rectify the next day. They then cancelled on me the next day. After much complaining from my end a plumber was sent round to rectify the following day and to be fair to them, they didn't charge me for the job in the end. A bit of saga for what seemed like a relatively straightforward job.