When it arrived, the bottom rim of the plunger had an imperfection in it, like a warping/dent. Regardless, I had a slow running vanity sink that I was fed up buying Drāno for as it never really solved the issue, and this was about the same price as a bottle of Drāno, so I had nothing to lose. Immediately, it dislodged a pile of crud in the pipe, and the sink started running faster. Another few goes over the next 30 minutes and the sink now runs like it was new 5 years ago. So, even with a visual imperfection, it worked absolutely fine.