The Lovely Pop Up Drain...

Did you know that pop up drains are made differently for vessel sinks or for sinks with overflow drains? I didn't. Live and learn.

I assumed that the young lady at Casa de Plomero would give me the right one for the sink, that I also bought from them.

So, LOOK, at the drain if you're buying one. If it's got a hole in the pipe under the stopper, then it is strictly for a sink that has overflow capabilities. If it doesn't have that hole, then it's OK to use for a vessel sink.

They ain't cheap so I hope I've saved you some money and aggravation.