This may sound like a stupid question (I'm new to plumbing terms), but for something like this. What diameter PVC pipe can fit into this?
For example, does this mean the diameter of the coupling itself is 2 1/2" and therefor can snuggly fit a 2 1/8" diameter pvc in it?
Or does this mean a 2 1/2" diameter PVC pipe can fit in it?