Hi, I'm new to the site and I have found this site to be very helpful! We have a Vogue Discovery 21' Round pool. It has two return holes and the skimmer. The old Returns have the threaded nut to tighten them down but someone previously used glue.
They measure 2 1/4" outside diameter. Is the hayward sp1023 the right ones to get? They all say 1.5" threads. I'm sure that's inside thread diameter but how am I sure it will have 2 1/4" outside diameter to fit the hole in the pool wall?