When my PB built my pool, they put in 1.5" and 2" return lines and a cleaner line - all just straight PVC piping. When they plastered, they simply cut off the extended PVC pipe at the edge of the plaster. While they left both return lines as is (smooth PVC pipe), on the cleaner line they inserted a white "cap" on the edge that provided a threaded end which enabled me to screw in my cleaner, fountain, etc. But I'd like to do the same to my return lines - so I can use a PoolSkim on the return (or fountain, etc.). Does anyone know if I can retrofit my PVC returns with one of these threaded caps, and where I can get them?